Azeroth has been changed forever with Patch 4.0.1. Sweeping class and talent changes, a new water engine, new UI, new abilities like Reforging, new glyphs, a new raid lockout system, new badge point system, new spell effects and more! www.MMO-Champion.com has done a great job of pulling a lot of the information together in one place if you want a preview, or you can just wait and experience it all yourself whenever the servers come back online. Official Patch Notes are available here http://www.worldofwarcraft.com/patchnotes/test-realm-patchnotes.html.
Soon we’ll feel the rumblings of the Cataclysm as our cities come under attack by the minions of Deathwing. Are you prepared?