This time around pg set up conversations between some of the prior founders and some of the applicants--to get a better feel for the teams, and to give them a chance to ask any questions about YC they had (including what to expect in the interview and how to best present their case--and maybe even who to pitch to, since sometimes pg is not going to like your idea, but rtm or tlb might if you pitch it right, and pg takes their advice seriously).
I was amused to find that one of the groups (one of the best we talked to, actually) was planning to work on the same area as our new product from a slightly different angle--I don't think they were entirely aware of how closely the functionality of their proposed product matched what we're about to launch until I told them). It's not at all unlikely that we'll contact them in a few months when we begin hiring (because them having written no code, and us having functional code in private beta with real paying customers, we do seem further along--but they did seem like a smart team, and if YC doesn't accept them, we might have a good place for them on ours).
I thought it was interesting, anyway. And since I've frequently stated that the single best thing about Y Combinator is spending a lot of time with the other teams, anything that provides more connectivity between founders is a win for everyone.