WoW - Patch Notes @ Official Site

The Before the Storm patch notes are available at the official World of Warcraft site.  Here's a few highlights.

Revamped PvP Honor System - This new reward system will allow players to accumulate honor points that can be spent like currency to purchase weapons, armor, and various other items beneficial for player-vs.-player progression.

New Talents - Each class will now have access to all-new talents in each of their three talent trees.

Looking For Group Tool - This new tool is designed to assist players in finding groups for instanced dungeons and quests.

Arena Skirmishes - Players will be able to queue for small-group, gladiatorial combat matches by speaking to the Battlemasters throughout the world.

And more!
You can read the entire patch notes here.