As someone who is socially withdrawn unless among friends, this sounds like a great idea. A quick, no-risk way of meeting people meaning people like me can feel a bit better about finding people to talk to. I've been to a number of conferences and, every time, I either limpet to existing friends or find a safe, out-of-the-way wall to lean against during lunch/ downtimes. This... sounds like it could stop that from happening. Neat!
Anyone else have any good ideas along these lines?