Battle Stance - Increases the armor penetration of all your attacks by 10%.
This is a straight up buff, and because Armor Penetration is a better PvP stat now than it is for PvE, this is clearly going to help. Considering armor reduction effects are now percentage-based, this buff is going to help quite a bit. Nothing exciting yet, right? Right. I hope you've got those brown pants on, because the next one is downright insane.
Shattering Throw *New Skill* - Throws your weapon at the enemy causing [ 50% of AP + 12 ] damage (based on attack power), reducing the armor on the target by 20% for 10 sec, and removing any invulnerabilities. 25 Rage, 30 yd range, 1.5 sec cast, 5 min cooldown
I just had to put that in bold letters and underline it. Aren't you glad I told you to wear brown? Warriors are now one of only two classes that can break a Paladin's Divine Shield or a Mage's Ice Block. It's a baseline ability, which means that all Warriors will have access to it. This improves Warrior viability in a Paladin-dominated Arena environment substantially. It's on the same cooldown as the aforementioned invulnerabilities, as well. This means that every time Paladins or Mages put them up, a Warrior can demolish it. Just in case you missed it -- Shattering Throw also deals damage and reduces armor (and it's likely used when in the armor penetrating Battle Stance!). Not only do you remove their precious invulnerabilities, you spank and strip them, too. That's just naughty.