@staffan: yep, exactly! This massive overhaul of Azeroth is as good as saying it as "WoW2" that there is no more point keeping WoW vanilla and TBC separated (and the zones as well).

I hope that's the path that they have chosen. They can keep WotLK separate, at least from the business perspective they can still get money out of it. But still, a "massive overhaul" will not convince some < Catac player to buy Catac? I doubt that. Not to mention, whether < Catac accounts buy Catac or not, they will still get the Cataclysm-Azeroth.

I really wonder how much of the original WoW vanilla installer are not needed anymore. Probably up to 80% are trash already. They can add the remaining 20% that are still required as part of Catac or as part of Patch 4.0. Then release as you suggested, a combined installer - at least Patch 4.0 and start from there.

If they want, they can still sell it for price of WoW vanilla + TBC (LOL).

Oh well... I hope I won't ever come to the point wherein I have to reinstall WoW from vanilla to Cataclysm...