Most Christian rock sucks because the artists (perpetrators?) think they can substitute lyrics about God for any form of musical or lyrical talent. If I want to hear about God, I go to church. If I want to listen to music, I want that music to be well written.
For an exception to this rule, see mewithoutYou. Earlier albums kinda (but not really) hardcore based, moving towards indie rock/pop with later efforts. Music and lyrics are simply astounding.
Also, 'mazing thread necro.