The patch notes for the newly-opened Cataclysm beta test have been updated as of build 12319. Full notes are available after the break.
Cataclysm Beta Patch Notes 6.30.10

Blizzard has confirmed that the third expansion for World of Warcraft – Cataclysm will change the landscape of WoW forever.
It’s a sadness that many of the beloved parts of the original game will be lost, but more importantly Cataclysm is going to erase some of the worst parts of World of Warcraft, and that is something to truly cherish.

Change is good…or is it?
Cataclysm will change the very face of Azeroth, leaving the world looking little like the one we know so well. Almost no zone will be left untouched and a new era of WoW will be upon us.

Hail to the King, Baby: In the upcoming Patch 3.3, Icecrown Citadel will be added to the game leading up to the final showdown with Lich King Arthas himself, and we got a look at what was in store.

In World of Warcraft: Cataclysm, we’ll be making lots of changes and additions to class talents and abilities across the board. In this preview, you’ll get an early look at some of the changes in store for the priest class, including a rundown of some of the new spells, abilities, and talents, as well as an overview of how the new Mastery system will work with the different talent specs.

Stats used to be relatively simple, and when the original World of Warcraft shipped it was easy for people understand which items they should choose to upgrade their character and make the most of their talents.