There's very little I like after TBC, most sets just don't feel much like my vision of the class, although the Mists cloth questing sets were really nice; I used the whitish one on my priest for some time. A couple of Mists tier sets are good, but as I only do LFR and the good colours are always normal/heroic, those will have to wait.
Priest: T5 (also have T1 when I feel like a change)
Shaman: Dungeon 2
Rogue: Vanilla greens in a Syndicate Rogue outfit, working on T6 (also have Dungeon 2)
Paladin: Warrior T1 recolour (also have T2, would like T9 when I level enough to go for it)
Warlock: T1 (considering Sunwell set when I level up)
Warrior: Cataclysm levelling dungeons gear
2nd priest: Primal Mooncloth (T1 recolour)
Hunter: Dungeon 2
Monk: Green 30-35 questing set
Hmm, I voted for TBC but it looks like I actually use more Classic than TBC, oh well, I like both about equally anyway!