Of course, Groupon is arriving to the party a little late. Facebook launched 'Deals on Facebook' last month. The beta service is still limited to US users at the moment: Atlanta, Austin, Dallas, San Diego and San Francisco are currently live.
Does it have the jump on Groupon? Possibly. Facebook makes it easy to invite all your friends along to your impulse meal or spontaneous night out - they're all housed on the same platform, after all.
But Groupon's mighty subscriber lists and established relationships with small businesses across the globe stand it in good stead. And we quite like this teaser advert too.