Update 11/23: I think that was a disaster of epic proportions.
Update 11/24: I should clarify. It wasn't disastrous because of the kiss. Or the simulated oral sex. Or the crotch grabs (his own or the stripper-pole girl's). Or the flipping-of-the-bird. Or the fall, which was amazingly ninja-like -- did not know that theater guys were rigorously trained in the tuck and roll -- and through which Adam sang well. What was disastrous to me was the batch of bad notes and overall awkward sounding vocals. I've never heard him sing a bad note, so that was shocking. It's a song that didn't translate well to a live version. It didn't help that the audio mix was bad on TV. (Reports are that it sounded better in the room.)
Update 11/24: Rolling Stone gave him a pass on the singing and loved the performance:
It’s already hard to remember what the world was like before Adam Lambert showed up, less than a year ago — but we can be sure it was a colder, drearier, and less pervy place, and moments like this epitomize why we’re glad to have this lady-stardust guy in our lives.
Update 11/24: HuffPo has video that should remain available, so I'll post it here for convenient reference. I've seen a slow-motion gif of the fall that is pretty cool and I'd like to share, but it's not legally postable. Adam's younger brother Neil was proud of the athletic feat:
On another note, ABC says they got 1500 calls complaining about the performance (not sure if it was the OTT sexuality or the musical quality). That's not very many, I don't think, considering the audience was something like 14 million.