This is kind of a rant(no wait... it IS a rant.) I have a new team with a warrior tank and he is getting pretty geared (33k unbuffed maybe 34 I forget). Anyways after a few heroics one thing I have noticed is:
1. AoE is AWFUL. See that pack over there? Ya you are going to have to TC and Shockwave before your dps start in with their AoE spells. Oops someone overaggrod? NP taunt and beat on that one. Ooops 2 adds went for healer? Shit! Hit AoE taunt. Fuck! Healer died.... I cant tell you how many times this has happened. Compared to Paladins warriors suck balls at AoE.
2. Single target is not so bad. Warriors need a lot of pregame warmup to do effective tanking. Once you establish aggro you are usually good to go, comparitively on my shaman/paladin team I dont have to wait at all and never lose aggro.

So what did I gain with a warrior tank? Spell reflect, which is F*ckin awesome. Uhm Shield Wall, ok paladins have that. Hmm, Last Stand. Charge? Yea kinda neat.

At this point I'm afraid to take my warrior to tank Ony10, even though he has the health/mitigation/avoidance to do it easily. I'm just scared of the whelps phase where I gotta keep them on me with 5 aggro magnet mages blizzarding. PuG people dont understand that waiting 3secs before you start dps is a good thing. Hell on my paladin as soon as I pull Ony I see 50k dots and shit going off. If it wasnt for misdirect Im sure Ony would splat the dps. I also want to do ToC Heroic, but I know the ghouls will just destroy my dps because my warrior sucks balls at AoE aggro. Le sigh. I should have used my DK tank that was already 80 for this group. =/