You certainly want to complete your game to the last level.

It makes you have to buy WoW key to complete your WoW game. You need to get World of Warcraft CD-key too. Those are the important things that will keep you in the game.

You can search over the internet to get some great offers on those CD-keys. You can easily drop your order on Cataclysm pre order and it will be delivered right away.