Facebook is bringing its social-networking might to the daily deals business with a pilot program that debuts in a handful of markets today. It could prove a game changer in the fast-growing business of offering deeply discounted deals for a limited time only.

Touted as no less than a “Groupon killer” by some observers, Facebook Deals is launching its long-anticipated daily deal offerings in five U.S. cities: Atlanta, Austin, Dallas, San Diego, and San Francisco. That's small potatoes compared to deals giant Groupon, which is in 500 markets, but Facebook has no plans to stop at a handful of markets, indicating in a blog posting today that it is looking to move into additional markets.

Facebook Deals will offer activities that Facebook users can enjoy with their friends, such as discounted trips to the bowling alley (a group of six could receive 75 percent off) versus the more individualized offerings that other daily deal sites tend to offer, such as a solo trip to get a bikini wax at the local spa. In Austin, Texas, known for its music scene, Facebook users will be tantalized with a deal for an All Access Experience, including backstage passes, for concerts at Austin City Limits Live starting in May.

“We've worked with partners and local businesses to help deliver the best social activities in your area,” Emily White, Facebook’s director for local, said in the company’s blog. “And once you've found a deal you like, having the deal on Facebook makes it easy to share, buy, and plan with your friends.

Daily deal companies have primarily used email as their way to connect with users, but the social-networking site is going its own way on this too. Although Facebook users who sign up for Deals in the pilot cities can opt to receive daily deal emails, the focus will be letting users find out about deals through friends, who will also be able to "like" or share a particular Facebook Deal through their news feeds, according to a story in the New York Times.

Deal-seekers can also gain access to individual deals from various local businesses and a comprehensive deals page for their area via a deals link in the left-hand navigation column of their Facebook dashboard.

Other daily deal sites also offer social-oriented deals: LivingSocial, for example, has offered salsa and salsa deals, which pair salsa-making classes with salsa-dancing classes; and Thrillist has offered deals for a strip (as in exotic dancers) and a strip (as in steak). But White predicts that the Facebook offering will distinguish itself by simply being offered on Facebook, the dominant hub for friend-to-friend communications with 600 million users worldwide.

“A lot of deal sites get that deals are social,” White told the Times. “But I wouldn’t say they are really well integrated with Facebook.”

Facebook says it will tap its own sales force to find businesses interested in offering Deals. It has also partnered up with a range of companies that offer daily deals already and will share their offerings. The partners include KGB Deals, the third-largest site behind Groupon and LivingSocial, the restaurant site OpenTable, PopSugar City, which tailors offers to female consumers, and Zozi, which specializes in outdoor activities.

If the 350 or so companies in the daily deal space are nervous about Facebook’s entry into what is predicted to be a $3.9 billion market in the next four years (up from only $873 million in 2010), they’re not alone.

The Times story also points out that users will be able to buy deals using Facebook Credits, which the company plans to turn into a major force in the online payment business.

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