there's been four mtvs for almost half a decade, as far as i remember
regular mtv that doesn't really show music videos that much anymore
mtv2 that also doesn't show music videos that much but sometimes has some excellent comedies (wonder showzen
), plus shows the cartoons that they used to play on mtv before TRL (beavis & butthead etc)
there's also mtv-x which i believe ACTUALLY shows music videos, not all of them good but you take what you get
and there was one other one that i don't really remember because i haven't had more than basic cable for years and it kind of sucked