If you jonesing for more information out of PAX, you can always take to the Official Forums. AutomaticZen took the time to write his impressions for everyone. He talks about dungeons and rifts among other things. Here’s what he had to say about the Warrior Souls.
Beastmaster - The Warrior Pet class, nothing more to say here.
Champion – This is the straight DPS warrior, the charge move Bull Rush, is in this tree.
Paladin – This is the first Warrior tank spec, focusing on blocking techniques using a shield
Paragon – The best way to put this would be Warrior/Rogue. The flavor text has a ‘Monk’ feel to it, but it mentions weapons so I’m not seeing it as an unarmed class. Lots of focus on Dodge, Parry, and Dexerity.
Reaver- The second tank spec is focused on threat generating DOTS, and has a good AOE focus is specced in a certain way.
Riftblade – I didn’t focus much on this one, wait for the video
Void Knight – The third tank class I noted. Anti-magic and some resistances.
Warlord- This is the Warrior buff class. Alot of buffs for your party, both active and passive. I’m viewing this as something a tank or dps would drop a couple of points in to give the group a helping hand in both PVE and PVP.