Owners of any Mac with an Intel processor—about 80% of all Macs in use, including yours—will be able to do simple, direct in-place upgrades to the new Snow Leopard edition of the Mac operating system, due out soon. This method will preserve all programs, files and settings without requiring any of the hard-disk wiping, temporary offloading of files and re-installing of programs that Microsoft is requiring to move to Windows 7 from its most popular current version, Windows XP.

Not only that, but Snow Leopard will cost you and other Leopard users just $29, which is $90 less than the Home Premium version of Windows 7. Apple also is claiming that the upgrade will be up to 45% faster than in the past and that it will actually free up an additional 6 gigabytes of hard disk space.

However, that doesn’t mean there won’t be obstacles or issues for some Mac users. Most important, owners of the other 20% of Macs, those whose models use older PowerPC processors—like the G4 and G5—won’t be able to use Snow Leopard at all. It’s the first Mac OS version that runs only on Intel-based Macs. So, if these folks want Snow Leopard, they’ll have to buy new machines, even though some of them bought their Macs as recently as 2006.

Also, although Intel-based Macs running the older Tiger version of the operating system can be directly and simply upgraded to Snow Leopard, Apple is officially requiring their owners to spend more for it. They have to buy Snow Leopard as part of a $169 boxed set that includes other Apple software they may not want.

Given the manual process of moving from Windows XP to Windows 7, isn’t it likely that there’ll be some third-party utility to handle it?

Yes. Seattle-based Laplink Software has announced that it will issue a new version of its PCmover utility—mainly sold for transferring data to new PCs—that will be able perform automated in-place upgrades to Windows 7 on an existing Windows XP machine, including the preservation of programs. I haven’t tested it yet, and can’t swear that it will work properly. More information is at laplink.com under “Latest News.”

Can you recommend software to remove trial/craplet programs? Something suitable for average users?

The one I have used with success is called “The PC Decrapifier,” which removes unneeded trial programs, add-on programs and advertising come-ons known as “craplets.” The software is free at pcdecrapifier.com. Note that it works only on PCs running Windows XP and Windows Vista. Before you use it, make sure to read the list of exactly what it removes, which is on the Web site.

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

Virtually everyone agrees that “OS X Leopard is far superior to Vista,” says Cook. He goes on to tout the Mac’s software. He speaks of compatibility and Boot Camp, which allows Windows to be run on a Mac.

Cook notes that Microsoft Vista’s failure at market–one of the greatest missteps in Microsoft (MSFT) history, according to Cook–has afforded Apple (AAPL) an unprecedented opportunity to win over Windows users to the Mac platform. He says Apple retail stores receive 400,000 visitors a day and that 50 percent of the company’s sales are now to Windows users.

Mac has outgrown the market 14 out of last 15 quarters, Cook continues. The Mac retail share has grown to 18 percent of U.S. retial sales, with a revenue share of over 31 percent, which means that one out of every three dollars spent on computers is spent on a Mac. Quite an achievement.

Finally, Cook points out that Macs now account for 47 percent of computers at universities. Apple has sold more Macs in in the last three quarters than it sold in all of 2007.

Virtually everyone agrees that “OS X Leopard is far superior to Vista,” says Cook. He goes on to tout the Mac’s software. He speaks of compatibility and Boot Camp, which allows Windows to be run on a Mac.

Cook notes that Microsoft Vista’s failure at market–one of the greatest missteps in Microsoft (MSFT) history, according to Cook–has afforded Apple (AAPL) an unprecedented opportunity to win over Windows users to the Mac platform. He says Apple retail stores receive 400,000 visitors a day and that 50 percent of the company’s sales are now to Windows users.

Mac has outgrown the market 14 out of last 15 quarters, Cook continues. The Mac retail share has grown to 18 percent of U.S. retial sales, with a revenue share of over 31 percent, which means that one out of every three dollars spent on computers is spent on a Mac. Quite an achievement.

Finally, Cook points out that Macs now account for 47 percent of computers at universities. Apple has sold more Macs in in the last three quarters than it sold in all of 2007.