[waterside81]

You're bang on with #1.

Our company was on Groupon NYC and they took their 50% cut of each Groupon sold (plus the merchant pays the credit card fees - don't forget about that. Your take is actually less than 50%). Luckily we had a bit of a math on our side as our markup on our products is pretty big so even after Groupon's cut, we still made about 15%. As of this writing, only 28% of our Groupons have been redeemed, so we're quite ahead. But I think our case is the exception - I have yet to hear too many stories about businesses thriving because of these social deals.