It's a fascinating concept, and a very clever exercise in game design, but the privacy issues really kill it for me. Of course they're not going to violate your info now - it's not worth much until they have an established userbase and a lot of info on all of them. The more successful it gets, though, the more valuable that information becomes, and the bandwidth costs will get them if the temptation doesn't.

Ironically, I might be MORE inclined to use this thing if I were NOT a Firefox user. That way I'd only be "playing" (and dealing with any instability) when I consciously chose to load up an alternate web-browser. But I suppose that's the exact opposite of this game's point.