I like both of them to be honest. I do think O'brien pretty much got shafted though. Basic situation if you're not familiar:
Leno had announced his retirement (a few years back) and that he was stepping down. He later had second thoughts and essentially wanted to back out of the retirement, but Conan had already been announced as the successor for The Tonight Show. So, they gave Conan The Tonight Show and moved Jay to a new 10:00 show. Problem is, at 10:00 most people just aren't ready for a late night show and ratings of neither show was doing great. They basically wanted to try to shift Jay basically back into his old timeslot where The Tonight Show WAS when he hosted it, and then shift Conan back into the later slot again. Effectively, "demoting" his show and giving Jay back the Tonight Show, in spirit if not in name. Conan, pretty much understandably, declined. While I haven't heard it officially announced, most feel that after Conan works out parting terms with NBC, the network will just give Jay back the show completely (in name and in timeslot).
I hope that Conan gets a good show somewhere though. Not a lot of openings at the moment with Kimmel on ABC and Letterman on CBS (neither host of which I particularly like), but I'm sure he'll end up somewhere.