5 months? i thought one month was bad...
Leadership XP- buy GoD. When you are a leader in a group you get special xp in addition to your real xp. You can use these xp points (i call them LA - Leadership Advancment's) to buy cool abilities like having the power to clearly mark one target for all of your group to see or to increase the rate at which your group regenerates hps.
New Zones- I think you must need to be lvl 50+ to fight in the new zones. I've been more interested in getting to the planes than trying out the new zones with GoD so all I can really say is that they are there.
Tribute System- you can turn in items (and money?) for tribute points and then trade your points for some cool buffs. The tribute buffs stack with other buffs and items, and i heard that they will automatically refresh themselves if you want them to so you dont' spend forever running back and forth between zones...
Berserker class- i'm sure you found this one out on your own...
There is more cool stuff that I, in my limited experience, can not tell you for certain, but when i posted this, no else had. Just a short reply to your answer. I'm sure more people will post better replys.