One of the things that is so interesting about AoC is the depth they go to stay gritty. Take AoC's tank, The Dark Templar.
From the AoC site:

"...the Dark Templar will go as far as to trade his very humanity to any dark being who will offer him a piece of the corrupted power that they possess."

That is some pretty evil shit. It kind of makes World of Warcrafts shadow priest look like a cartoon. The official site continues, "...the Dark Templar is also quite a sadist."

There is more information about the Dark Templar at Ten Ton Hammer

From that interview it seems like AoC is at least attempting to balance the need for a tank with a tanks desire to do damage. Jørgen Tharaldsen, Product Director for Funcom says "The Dark Templar can also remove his shield, and instead focus on holding magical talismans in the offhand, which will give him additional combat effects like bonus damage or procs" and "we have a mode in the game called Frenzy, and a Dark Templar going into this mode can deal around 150% extra damage, [but you take] three times the damage if someone hits you."

Sounds sweet. Ten Ton Hammer will have a class review every two weeks, stay tuned for more.