I have a blood elf mage and love the arcane torrent, its handy in those situations where you go oom and that mob needs just one more fireball to curl up and die, or I can frost nova and run away! I actually can't believe how many times it has saved me.
I started to level a troll mage but gave up because a 3min cooldown seems so long, and it only runs for 10secs anyway. Plus when he gets hit or takes fall damage, the troll makes this really annoying ribbit noise.... like a frog.