Well he certainly knows how to kiss @ss, like a real star.
I kind of have to seperate out the fact that he seems like a potential jerk from his performance though. I'm not sure he's the best singer on the show, but he's certainly a creative enough dude.
As for the hand in the air thing... wasn't that part of Alanis' schtick? I assumed he was just familiar with her performance style, even if he had to rearrange the song for his own voice.