Before Cataclysm launches remember to:

– Empty your bags
– abbandon all old quests in your log
– train flying in Azeroth (this will cost 4000-5000 gold depending on your reputation)
– set HS to major city (Stormwind/Origmar)
– do 25 quests(preferably dailies) and turn them in when Cataclysm goes live

Here are just some of great tips on how to be prepared for when Cataclysm goes live. Follow them an you’ll have a head’s start infront of all the other players. If you really want to be ahead of all the other players check out this guide http://tiny.cc/levelingguide