It looks neat, though I'd worry about being gypped out of my money:

1. I don't know your or your site from Adam (no offense intended, honestly) and your site hasn't been around long enough to have a rep. There aren't any "trust markers" around to help me decide whether or not to trust you with my money.

2. I'd worry about, for example, some of my facebook friends not responding in a timely fashion or forgetting to do it, and the FAQ makes it sound like one person not responding would prevent me from getting my money back.