I think I'm all WoWed out, really don't miss it at all. If Cataclysm turns out to be a great expansion then I might try it, as playable Goblins sounds fun and exploring new content is always good. But if it's just more levelling grind, badge grind, raiding grind, rubbish PvP and ever moving goalposts like the last two xpacks then meh.
Since the cataclysm itself looks set to radically alter all the original Azeroth zones it means that vanilla WoW as we once knew it will be gone forever, and perhaps it's a good time to walk away remebering it as it was. I think the only thing that could save WoW for me is if they somehow found a way to make the PvP fun again, but given the gear arms race that has happened over the years I don't think that's even possible anymore.