You can send Ms. Malubay home when you pry her from my cold, dead hands!!! (Yeah, I know she's not the greatest singer, but she's still half the reason I'm tuning in to that show.) I say, send home cute but talentless David Archuleta.
Dang me if I don't wholly agree with you, dude. Archuleta is a voice looking for some guidance. I'm of the opinion that his rendition of "Imagine" a few weeks back was wholly a fluke (Simon called it "a vocal master class"). He hasn't been anywhere near that level since.
I've read that his father, Jay, is an overbearing "stage father" who berates him from time to time. I think it interesting that Simon last night said that he doubted David picked his song for himself because it wasn't "him." I think the show enjoys having the obligatory, weekly cutesy comments from David when he can do his "gosh-oh-gee" boyish laugh -- the pre-pubescents squeal in girlish delight each time, but it does smack of being in the same category as "Smile, Louise!" He seriously pales in comparison to David Cook and Michael Johns. In time, though, he may totally surpass them as a vocalist.