What expansion did you enjoy the LEAST?

[Keren]

I guess wotlk was the expansion that brought wow to the decline - an epic background story that was less than adequat showed. Stupid easy entry Raid that most guild cleared in tbc gear and the argent dawn campaign and raid felt so bad. It was moved to icecrown because server counldn't handle dalaran otherwise - degrading the whole cristalsong forrest to a useless zone.
ImhO the other bad thing was introcing the raid finder in Cataclysm. And last, on a more personal reason, MOP. Pandas, Monks and a chinese themed artstlye. MoP was the killer for me...

[Zaelsino]

Wrath or Cata. Wrath started off okay but went on to set some very bad precedents that Blizzard still haven't managed to break, like unabashed content droughts. Cata's lowbie experience was (and continues to be) fun, but it apparently came at the cost of a very uninspired end game.

Hard to say for Warlords, but this is definitely the most bored I've ever been with the game. The first patch being a not-so-glorified bug fix didn't help either, especially since MoP's first two patches were solid and engaging.

[mvaliz]

OP: Which expansion did you enjoy the LE...
Me: Cataclysm
OP: ...AST...

[Mafic]

Right now for me it is WoD.

6.2 may upgrade WoD to be better than Cata.