David is my favourite. I like that he is taking the crappy songs they give them and finding newer versions of them. Even if his Billie Jean was modelled on someone else's, it was still way better than just doing karaoke of the original.
To me this shows that he is modern with his musical tastes. I don't think too many of the others can say that. Some great singers, but if they can't get modern then do we care? (hello? Taylor Hicks? Are you out there??)
The guy who won Canadian Idol last year, Brian Melo, was great at having a more modern alternative sound that certainly better suits my musical tastes than a lot of the other tripe.
Here is a youtube of Brian doing Karma Police, which certainly went over well on Canadian Idol:
http://www.youtube.com/watch?v=jat_Q1t2G3A&feature=related