Onewholivesforchrist: I don't think that can be put any better. Apart from the song writters themselves.
Just because there's no immediate and noticable reference to God or Jesus don't mean they're not a Christian band. I've actually met Mike and asked him if the band was a Christian band and he himself said that they are Christians in a Christian band. And if you know the bible well enough you can see that there is plenty of reference to God which onewholivesforchrist has clearly pointed out.