*shrug* I don't see the big deal, other than the "bandwagon" argument (which GHWT is doing for RB, and the other one, can't remember the name, is doing from both RB and GHWT). Besides, if the market can handle 4,132,314.4 FPS games, it can handle three or four music game franchises (especially if the controllers are compatible.)
I know it's uncool to be Christian or like Christians/Christianity nowadays, but I think there is a huge market/demographic who would eat up a Christian rock game or a Country game/disk. Some Christian rock actually does rock.
Speaking of which: is Fireball Ministry "Christian" rock?