One of the nice things about WoW is that it allows you a variety of choices for your character. You really aren't pigeon holed into one thing or another. There are some cases in the upper echelons of the game and theory crafting where one weapon or armor choice becomes superior – but that's only if you want to take the game to such a level.
And even then, min-maxing to that extent isn't really necessary to be successful in raiding anymore.
I've come across this in my play recently. My weapon of choice (and hence the forever awesome Christopher Walken music video attached to this article).
As a Shaman I have a choice of various slow 1H weapons, giving a variety of different stats that I'd like to have. When entering the starting zones of Wrath I can pretty much find any combination that I want to fit my needs. As a protection Warrior I've found the same thing, even at times finding it more advantageous to use a DPS based weapon over a Def based weapon.
For the Shaman (which I need to point out is just my favorite alt at the moment) my weapon of choice has shifted away from slow maces to whatever sexy fist weapon I can pick up. The DPS output is roughly the same, if not better in some cases, and I just like the way it looks.
Yes, I said it. And I'll take the beating that's about to begin.