There's a HUGE difference between a band who are Christians, and a Christian Band.
Christian bands play songs about Christianity. They're basically exploiting a certain media, in this case music, to preach. Regardless of whether you're a Christian or not, I think that's plain wrong.
Bands with Christian members... who gives a fuck. That's up to them, let them be.
18/12 Black Sabbath
14/1 Iced Earth
18/1 Lamb of God