I have a feeling that the monetization model is based entirely on the referral system offered by Revolution Money Exchange. The thing is that RMX offers a bonus of $10 for every new recruited member so this $10 sounds very much like what they are going to use for the tips. I only hope they will not see tips stopping after all the users are out of their initial $10. - Svetlana Gladkova from FriendFeed MT Plugin