So it's been out for 2 years now. I wasn't real impressed in the beta, but 2 years later the game is running nicely and is actually pretty fun, especially if you're already a D&D fan. I got a 10 day trial account from a friend, and have been playing for 3-4 days now.
The combat is pretty close to how I expect Age of Conan's combat to be like. It's not turn- or tick-based (surprisingly) like WoW, it's real time, and you swing or shoot your weapon manually. If you get a bigger weapon like a greatsword, you can even hit multiple targets at once, just like in Age of Conan. However, hits are still based on dice rolls, so unlike Age of Conan, you can swing your sword straight through an enemy and it might not hit (based on your roll and their armor). However, I'm used to how D&D works, so it actually makes sense to me.
The combat is actually very fast paced, probably the fastest paced combat I've played in an MMORPG. It's really lively and realistic looking too. If you come across a group of kobolds, for instance, they don't just run up and start hitting you while standing still. They actually weave and jump around so they are harder to hit, which means you are running around trying to hit them, so it looks pretty realistic.
As far as I know, the only PvP is arena style. Apparently there are deathmatch and CTF modes, but you can also just jump into the ring with a friend and start killing each other without going through any menus or anything. Being D&D, PvP doesn't play a large part, obviously.
The game basically consists of nothing more than getting a quest and going into a dungeon. The whole game so far takes place in a city, so the dungeons are sewers, giant cellars and the like. The aesthetics and gameplay remind me a lot of NWN (but with much better graphics, obviously). You could basically consider it to be like NWN the MMO, only with real time combat.
One other thing... since it's D&D, it takes a while to level. However, you get something like 4 action points per level, which you can use to buy enhancements for your character. These are kind of like talents. One might give you a +1 to hit with melee weapons, another might give you an activated ability that does more damage, or you might raise a stat, etc. Pretty cool.
So far, I really like the game and might get an account after the trial ends. I think it's only $9.99 a month, which is what UO used to cost, so it's a pretty good deal, and I already got the client for free.