And so the company today said that beginning Friday, “select markets” can preorder Windows 7 at a more than 50 percent discount. In the U.S., that means Windows 7 Home Premium will set you back about $50, or Windows 7 Professional about $100. A “screaming deal,” Microsoft calls it.

The promotion runs until July 11 in the U.S. and Canada and until July 5 in Japan, or “while supplies last.” If you choose not to preorder an upgrade copy, you’ll obviously pay a bit more for Windows 7 when it finally ships on Oct. 22. Existing XP and Vista customers in the U.S. will be able to purchase Home Premium for $119.99, Professional for $199.99 and Ultimate for $219.99. New customers will pay $199.99 for Home Premium, $299.99 for Professional and $319.99 for Ultimate.

Pricey, but about 8 to 17 percent less than Vista. Said Brandon LeBlanc, Microsoft’s in-house Windows blogger, “Overall, customers will be paying less and getting more with Windows 7.”

For their sake, let’s hope so. Especially if they paid retail for Vista.

Here are a few questions about computers I’ve received recently from people like you, and my answers. I have edited and restated the questions a bit, for readability.

A friend’s Windows XP PC is having troubles. He wants to copy its contents onto a separate backup drive. Will he encounter problems if he tries to transfer this material to a Windows 7 unit he plans to buy when available?

He should have no problem at all with the data files, such as Office documents, music or photos. However, it may not be possible to transfer the programs and settings without reinstalling them from the original disks or downloaded installation files. And he may also have to re-install any patches or updates to these programs. Microsoft plans some sort of system to make this process simpler than it might be, but I don’t yet know how it will work.

I am not a super techie but would like to view Internet videos from my computer, attached to my TV. What do you recommend? Is there a system or a product that would be best for my needs?

You very likely don’t need any special product, other than the right cables and, if need be, adapters, to connect your computer and your TV. This choice depends on the details of your computer’s graphics capabilities and output ports, and the input ports and capabilities of your TV. All of this is much easier if the PC and TV are relatively modern — say, two years old or less. But, whatever their age, you should visit a competent electronics store that sells cables, provide the staff with the details of the two products, and seek their specific advice.

With the rising popularity of the netbook, do you know, or expect, that Apple will come out with a netbook? I would be very interested in getting one.

I know of no such plans. In fact, Apple officials have said they have no interest in producing a netbook, which is a small, inexpensive laptop, and have disparaged the category. However, Apple is quite secretive, and sometimes enters categories it had previously laughed off. Also, there are persistent rumors that Apple is working on a flat, tablet-style computer — perhaps a much larger version of its iPod Touch pocket-size device. If these rumors prove true, such a tablet might compete with netbooks.

Our daughter has asked for nothing but a Nintendo DS game system for more than a year now. Her birthday’s in two weeks. She says she’d be happy with the cheaper DS Lite, but is it worth going with the new DSi for $40 more? Do you think the DS Lite will become obsolete, in terms of new games for it?

Obviously, this depends on your budget, and I don’t think there’ll never be another new game for the DS Lite. But if the $40 price difference isn’t an obstacle, I’d go with the DSi, because I assume that, over time, more and more games and other software will emerge that will run only on the higher-end model.

• You can find Mossberg’s Mailbox, and my other columns, online free of charge at the new All Things Digital Web site, http://walt.allthingsd.com.

Linux on netbooks isn’t going away though. In fact, software and hardware companies have been making big investments to improve Linux netbooks. For the past week, I’ve been using several flavors of Linux running on netbooks — Ubuntu, Hewlett-Packard’s Mi (which is based on Ubuntu) and Moblin, created largely by Intel and not yet available commercially. In all cases, the Linux netbooks failed at some basic functions that any laptop, no matter how tiny and inexpensive, should be able to handle, like working with printers. At the same time, Mi and Moblin have impressive graphical user interfaces well-suited to the habits of typical netbook users, like checking email and accessing social-networking sites, as well as the small screens and low horsepower of tiny laptops. In addition to Linux, all of the computers shared the standard features, or lack thereof, common among netbooks, including compact keyboards and no DVD drives.

H-P’s Mini 110 Mi Edition

The most polished of the products was H-P’s Mini 110 Mi Edition, a new model with a 10.1-inch screen that H-P will begin selling on its Web site for $279.99 on June 10. That’s nearly $50 less than what H-P will charge for the Mini 110 running Windows XP, which will come with a 160-gigabyte hard drive instead of the 8-gigabyte solid-state drive that will come with the Mi edition.

The striking thing about this netbook is the slick graphical user interface created by H-P that runs on top of Ubuntu and first began appearing on H-P netbooks early this year. Instead of a traditional desktop like that found in Windows and the Mac, Mi (pronounced “me”) arranges commonly used applications and content on a screen called the “dashboard,” which looks like a personalized Web page and lists recently received emails, fresh thumbnail images of favorite Web sites, and a Web-search toolbar.

The Mi home screen is a clever way to make the computer seem alive with on- and off-line content, which is fitting since netbooks are designed for on-the-go Internet activities. It’s also tailor-made for the small screen size of netbooks.

A more eye-catching iteration of Linux is Moblin, which I tried out in test form on an Acer netbook; it is expected to ship on netbooks by the end of the year. Moblin has a menu of icons at the top of the screen, the most interesting of which leads to the M-Zone, a home screen that displays calendar appointments and favorite applications alongside snapshots of recently visited sites and a continuous feed from the user’s Twitter network.

An icon called “People” leads to a list of instant-messaging buddies, while another, called “Zones,” let me organize all the applications I had launched into different virtual workspaces, which is useful for hopping between various tasks on a small-screen device like a netbook.

The look and feel of the standard Ubuntu system, without the Mi interface, is more commonplace. I tried out a Dell Mini 10 with a 10.1-inch display and 160-gigabyte hard drive that sells for $349 on Dell’s Web site. The Mini 10 ships with version 8.04 of Ubuntu, which resembles Windows XP, with its desktop, taskbar and pop-up menu system. Ubuntu, in some cases, seemed to overestimate the size of the Dell Mini’s display: A window for configuring wireless-networking capabilities was so large it bled off the screen, and I couldn’t access all the buttons on it. I also installed on the Dell a new version of Ubuntu Netbook Remix, which works better on small screens. Since a Windows XP version of the Dell Mini 10 sells for the same price as the Ubuntu, I can’t see a compelling reason to choose the Ubuntu option.

All the netbooks I tried had compatibility problems with other external devices. The netbooks couldn’t load the software drivers to let me print to my Canon and Dell printers. I couldn’t load pictures over a USB cable from my Canon PowerShot SD750 digital camera. I was able to get my pictures on the machines by plugging a storage card from my camera directly into the netbooks.

Canonical, the London company that oversees development work on Ubuntu, says it is improving the system’s compatibility with various devices. Intel says it is unfair to judge Moblin until it is commercially available.

Some key applications currently don’t run on Linux, like Apple’s iTunes, which makes it difficult to load music files onto iPods from the netbooks. While the Linux laptops didn’t run Microsoft Office, they came with OpenOffice, a free package of word-processing, spreadsheet and presentation applications that allowed me to open and modify basic Word and Excel files.

The companies behind Linux netbooks have made great strides in improving user interfaces, but until they can achieve similar breakthroughs in how the machines work with other devices, Windows netbooks are still a better deal.

• Email nick.wingfield@wsj.com. Walter S. Mossberg is away and will return next Thursday.

Though Windows 7 is expected at market by the end of the year, the United States military has set that as a deadline for its migration from Windows XP to the “worthy, but largely unexciting” Windows Vista and from Office 2003 to Office 2007.

The Army has been testing Vista since 2006 and its decision to move forward with a migration of its 744,000 desktops–on both classified and unclassified networks–was apparently driven by the OS’s improved security. “First, they see real value in Windows Vista’s improved security architecture,” Microsoft senior director Gavriella Schuster said in a statement. “Second, it shows large organizations have unique needs and timetables for deployment. These things take time–they have been rigorously testing internally–and it makes sense that they have approached deployment in a measured and well-planned way, especially given the number of seats they are migrating to Windows Vista.”

Now that the marketplace has abandoned Vista, is Microsoft making preparations to abandon it as well? Earlier today, a Microsoft executive suggested that might be the case, hinting that the company could be planning to ditch Vista soon after Windows 7 ships. “We are still not sure if [computer makers] will be able to ship Vista once Windows 7 is made available,” Richard Francis, general manager and Windows Client Business Group lead at Microsoft Asia-Pacific, told IDG, adding that support for all versions of Vista will end in April of 2012.

An interesting disclosure given that Microsoft (MSFT) hasn’t yet detailed official plans for Vista, post-Windows 7. With the poor reception the OS has received in the market and Microsoft’s efforts to redeem itself with Windows 7, it certainly wouldn’t be surprising if the company wanted to remove Vista from the shelves as soon as Windows 7 arrives. Then again, it wouldn’t be all that surprising if Microsoft left the Vista packages there for a while–tucked away behind some copies of Windows XP, of course.

UPDATE: Responding to my request for comment, Microsoft said that there is no hard and fast date end-of-sale date for Vista. The company noted, however, that OEMs will have the option to pre-install and retailers will be able to sell whatever versions of Windows they choose until that date is reached. Microsoft’s statement in full, below:

We have not made any final end of sale decisions for Windows Vista.

Microsoft Support Lifecycle policy provides a minimum of 10 years of support for Business and Developer products. Mainstream support for these business and enterprise versions of Windows Vista will be provided for five years, or for two years after the successor product is released, whichever is longer. Currently, Mainstream Support for these products is scheduled to end on April 10, 2012.

For Consumer products, including consumer versions of Windows Vista Ultimate, Home Basic and Home Premium, Microsoft will offer Mainstream Support for either a minimum of five years from the date of a product’s general availability, or for two years after the successor product is released, whichever is longer. Extended Support is not available for Consumer, Hardware, and Multimedia products. Most of these products will also receive at least eight years of online self-help support.

During Mainstream Support, customers have access to no charge and paid support, security updates and non-security hotfixes. Extended Support for business and developer products will be available until April 11, 2017. During Extended Support at a supported service pack level, customers can access paid support, security updates and online self-help. Non-security hotfixes are available to customers who enroll in the Extended Hotfix Support program within 90 days of the product entering Extended Support.

Now that the marketplace has abandoned Vista, is Microsoft making preparations to abandon it as well? Earlier today, a Microsoft executive suggested that might be the case, hinting that the company could be planning to ditch Vista soon after Windows 7 ships. “We are still not sure if [computer makers] will be able to ship Vista once Windows 7 is made available,” Richard Francis, general manager and Windows Client Business Group lead at Microsoft Asia-Pacific, told IDG, adding that support for all versions of Vista will end in April of 2012.

An interesting disclosure given that Microsoft (MSFT) hasn’t yet detailed official plans for Vista, post-Windows 7. With the poor reception the OS has received in the market and Microsoft’s efforts to redeem itself with Windows 7, it certainly wouldn’t be surprising if the company wanted to remove Vista from the shelves as soon as Windows 7 arrives. Then again, it wouldn’t be all that surprising if Microsoft left the Vista packages there for a while–tucked away behind some copies of Windows XP, of course.

UPDATE: Responding to my request for comment, Microsoft said that there is no hard and fast date end-of-sale date for Vista. The company noted, however, that OEMs will have the option to pre-install and retailers will be able to sell whatever versions of Windows they choose until that date is reached. Microsoft’s statement in full, below:

We have not made any final end of sale decisions for Windows Vista.

Microsoft Support Lifecycle policy provides a minimum of 10 years of support for Business and Developer products. Mainstream support for these business and enterprise versions of Windows Vista will be provided for five years, or for two years after the successor product is released, whichever is longer. Currently, Mainstream Support for these products is scheduled to end on April 10, 2012.

For Consumer products, including consumer versions of Windows Vista Ultimate, Home Basic and Home Premium, Microsoft will offer Mainstream Support for either a minimum of five years from the date of a product’s general availability, or for two years after the successor product is released, whichever is longer. Extended Support is not available for Consumer, Hardware, and Multimedia products. Most of these products will also receive at least eight years of online self-help support.

During Mainstream Support, customers have access to no charge and paid support, security updates and non-security hotfixes. Extended Support for business and developer products will be available until April 11, 2017. During Extended Support at a supported service pack level, customers can access paid support, security updates and online self-help. Non-security hotfixes are available to customers who enroll in the Extended Hotfix Support program within 90 days of the product entering Extended Support.