After all the threads I've read mentioning cookies...and it's not on one persons list here?
High on my list would be:
-Community (strange notion in a MMO, I know!)
-Gameplay (always helpfull in a GAME!)
-Story (Bioware, so not too worried there)
-Meaningful PvP (realy tired of the WoW formula...Queue, grind, gear, repeat. Give us areas to control and defend DAoC style)
P.S. Order of importance may change due to hunger.