I picked up a DAoC 14-day trail to tinker with after being contacted about submitting a resume for their web development... that evolved into two separate accounts that we play in our household now.
I started on the original Ultima Online back in the stone age of online RPGs and my son was a beta tester for Everquest. I didn't expect to like DAoC because I felt like the whole King Arthur Camelot bit was way overused, but this game doesn't even attempt to go that route.
They've done a great job in balancing the game play between leisure players, hack-n-slashers and player killers. The Realm vs Realm play is pretty high on everyone's list of features, and they have straight player killer servers running as well.
The development team also launches in-game story arcs with new quests and items on an ongoing basis, which means you can get new content without constantly buying expansions. They're also very responsive to feedback, compared to most other online games I've been associated with.
It's also way cool that you can make half a dozen characters on different servers - gets confusing if you do, but having that option to experiment, play on different servers, in different realms, using different character classes and races, means you have a good chance of not being bored. I play mostly solo since I have a day job and all, and that's been fun as well. I have about a dozen characters in two realms at the moment, trying to sort out what style of play I enjoy most. (so far I can say Heretics in Albion rock if you like to play a spell caster who can also defend themselves with heavy mace-like objects, and surprisingly, I'm having pretty good success with my Valewalker and Warden in Hibernia - just started a Ranger last weekend and he's loads of fun as well).
The in-game features for housing, guilds and groups is also pretty nifty. Perhaps all games have this now but when I left off playing MMORPGs in 2001, no one had in-game player-owned housing and none of the games directly supported player guilds - those were something that players did all on their own.
I've enjoyed it - my first 6-month subscription is about to run out and in that time two older expansion packs for DAoC have been dumped into general download for free, the game interface has been improved twice, classes have been improved, I've gotten in-game freebies and the periodic free level qualifications forgive me for working too many hours and going 5 or 6 days without playing.
I fully expect to be playing this game for at least another 6 months, maybe longer - I'd like to actually get to where I know what I'm doing! heh. But yeah, I'd recommend it - it seems to adequately cover all styles of play - from hard core, bot-toting thrash masters to once-in-a-while weekend warriors who just have their puppies...