The launch is not a surprise, since the Chicago daily deals company has been testing the technology in Philadelphia for the past few months.

Customers who opt in to Groupon Rewards will earn points when they spend money at a participating merchant using the same credit card or debit card they have on file at Groupon.com.

Once a customer spends a predetermined amount, a reward is unlocked to use during a future visit. All of the recording and accounting takes place behind the scenes, and doesn’t require customers to show receipts or check in on a mobile device.

Groupon says the program will also seamlessly tie in to a merchant’s point-of-sale system, and is available to any U.S. merchant, regardless of whether the business has previously run a Groupon deal.

Other companies are also working on similar loyalty solutions.

Earlier this week, I wrote about Belly raising $10 million to create a mobile-app-based loyalty program. And, Kirkland, Wash.-based Pirq also announced this week that it is giving Apple’s Bay Area employees access to daily deals.

Since launching in August, Belly has signed up 1,400 merchants in eight markets, and is adding an average of 100 more merchants each week. Additionally, it has more than 200,000 active users, who have checked into business more than 800,000 times.

The business draws a little bit from Foursquare, because it requires users to check in to earn points; and also draws a little bit from Groupon, because of its focus on local commerce.

But Jeff Jordan, a partner at Andreessen Horowitz, argued that Belly is not at all like Groupon. “It’s the anti-Groupon,” he said. “Groupon is doing lead generation through discounting. … What Belly is trying to do is loyalty.”

The difference, Jordan said, is that Belly doesn’t require merchants to offer discounts to get consumers to come back.

For example, a Chicago comic book store owner is letting shoppers punch him in the stomach; a Washington, D.C., Ben & Jerry shop is giving away a chance to eat ice cream with Jerry after 200 visits; and a barber is handing over the clippers to frequent customers, who will shave off his own beard.

Jordan, the former chairman and CEO of OpenTable and former president of PayPal, said there are four reasons why he was attracted to the start-up:

1. The management team: Founder and CEO Logan LaHive previously worked at Redbox, and before that, Pay By Touch, the biometrics payments company that raised $350 million in capital before failing.
2. Product execution: Jordan said both merchants and customers like the product. Merchants must install an iPad at the register, where consumers can check in to earn points by scanning a bar code from their phone or a loyalty card.
3. DNA of the investors: Before Andreessen Horowitz got involved, LaHive incubated the company in the offices of Lightbank, the VC fund created by Groupon founders in Chicago. Jordan believes that the one who gets to market fastest will win in this market. Belly has that in its DNA.
4. Connected retailers: Once retailers have an iPad in every store, there will be additional opportunities for Belly to roll out other services.

LaHive said the capital will be used to fuel expansion into new markets and to develop new services. To date, the company has raised $13 million.

Belly charges merchants $50 to $100 a month for the service, which includes an iPad, a case and lock for the iPad, marketing materials, and data and analytics to manage their business better.

Belly @ Berry Austin from Bellycard.com on Vimeo.

In the past, Yahoo has used killer lasers and giant afros and has even tried a dog rising from the dead to brand itself.

Also, of course, there was the yodeler.

That was in 2003, in a clever television commercial that featured Yahoo’s famous sound, as rendered by yodeling champ Taylor Marie Ware (by the way, if you click on the exclamation point on Yahoo’s homepage, it still emits an annoying male yodel).

Now, in what many sources at the company said is a major push, Yahoo (YHOO) is working on a massive plan to overhaul its brand in order to repair a damaged public image and focus consumers on what defines Yahoo.

The effort is being spearheaded by newly installed Chief Marketing Officer Elisa Steele.

To take on the task, she has hired both well-known brand consulting firm Landor Associates and an outside consultant named Penny Baldwin, who was a former top exec at brand and ad giant Young & Rubicam.

Yahoo had formerly been using Ogilvy & Mather and Siegel+Gale to work on strategic branding issues. Ogilvy is still working with Yahoo, sources said, but it is unclear if Siegel+Gale remains in the mix.

The new branding of Yahoo, said several people close to the situation, might be built around the latest relaunch of its main homepage design.

The important front-page redo had been delayed by CEO Carol Bartz when she took over in January and is now slated for the fall.

Many themes have been considered to depict Yahoo in the future, many along the lines of Yahoo still being a key hub destination for Internet users.

Those possible directions were discussed at a recent off-site meeting of Yahoo’s top execs, led by Steele, who ran through the tangled history of Yahoo’s marketing efforts and showed off some rough ideas for the future.

One motto considered, among several: Yahoo as “your home on the Web.”

Whether it is going to be a sweet home or not is unclear, and does depend on exactly how much Yahoo is prepared to spend on this rebranding effort.

Microsoft (MSFT), for example, is in the midst of a $100 million marketing campaign around the recent relaunch of its Bing search service.

And Google (GOOG) has a brand that hardly needs any introduction–and on which it has spent very little marketing money–in that its name has become the verb that means “search” on the Web for most consumers.

Yahoo’s branding campaign will certainly have to be a big deal, given that it is one of the top Internet sites in the world and has massive name recognition.

And Bartz has been vocal about the importance of touting Yahoo as a well-known brand, even as she has said a lot internally and externally that she detests purple.

(That has long been Yahoo’s main color and also mantra, as in “bleed purple.”)

In an onstage interview with me at the seventh D: All Things Digital conference in late May, I asked Bartz about the image of Yahoo being broken and how she would change that perception and revive its innovative spirit.

“The best way to change the perception is to do a good job and then talk about it,” she answered at D7. “We just have to get our story out there; we have to continue to appeal to the people that come to us, and frankly, at some point people get sick of having us as the underdog and say, ‘Thank God, Yahoo’s back.’”

Well, that could depend on how well its upcoming branding campaign works or not, which must also be based on the product and business strategy Bartz settles on in her rejiggering of Yahoo.

Tomorrow morning, Bartz will preside, along with Yahoo Chairman Roy Bostock, at its annual meeting in Silicon Valley, although it is doubtful she will unveil any grand plan then for marketing or other major company strategies.

So, until the branding plans are unveiled, here are some of the more memorable Yahoo advertising efforts.

Yodel:

Lazarus the Dog:

Killer Laser:

Afro-tastic:

Odd Advice-giving Canadian Yahoo Creature:

[Belly Yodel photo courtesy of Yodel Anecdotal on Flickr]