I actually love Natalie Dessay's performance of Glitter and Be Gay the best. Actually, just one of her performances as some others have her way overacting. It's on youtube and it's the one where the uploader says he/she does not know the date of when it was recorded.
Cook's rendition was wonderful as well.
Chenoweth's was a different take and her dominating stage presence and comedic timing can't be denied. I know some don't like her technique on the song (she seems to use the whistle technique quite a bit), but it seems people eat it up. I'm sort of hoping that she'll be able to tone it down a bit from the Lincoln Center Performance, but I don't think she knows how to tone it down.
"[Gore] was widely perceived as arrogant. If you know something, you're not smart. You're a smarty-pants. It's annoying. People get annoyed with your knowledge. It goes back to high school, to not doing your homework ... 'There's something I should know, I don't know why I should know it but someone knows it and I don't. So I'm going to have to make fun of him now.'"
-Sarah Vowell, The Partly-Cloudy Patriot