From DPS PoV, Frost is so far ahead of Fire I wouldn't call Fire viable if you are doing any sort of progress raiding. Arcane is in the mid, but unless you really like Arcane there's no real reason to play it either.
Though if your guild is casual, it doesn't really matter what you play.
MMO-Champion Rules and Guidelines
Frost is good
(i mean frost dk ofc)
You think you do, but you don't ©
Rogues are fine ©
We're pretty happy with rogues ©
Haste will fix it ©