Defies the definition of MMORPG, but if you can look past that, this game is awesome.
This game features 6 races, 11 classes, and all the customization you would expect from a D+D based game. Stat points, skills, feats, enhancements, and spell loadouts can all be customized. Customizing can lead to an awesome character or a really screwed-up character, so for those who lock up at all the arcane D+D math, there are pre-built paths, three for each class, which will make your character OK, but not as good as a well-tuned, customized character.
Classes can be played in different ways, but they tend to fit into specific roles in a party. Clerics and Favored Souls are healers, Sorcerers and Wizards are offensive casters, Paladins, Fighters, and Barbarians are tanks, Monks and Rangers are damagers, Rogues are trap monkeys, and Bards are the support class. Finding a well-balanced party is crucial to success, and finding a party is easy thanks to the ability to press a key and see every recruiting party on the server.
The adventures start easy and very linear, but soon become more difficult and in some cases labyrinthine. Here's a hint: Don't try "The Pit" without a guide. Combat is awesome, with frenetic pace and tight controls. Though non-spell classes have pretty simplistic controls (as in, mash left mouse button), combat can be fairly complex because this game embraces the idea of moving around during combat. Outside of combat, there are traps, which basically have a control box that the rogue must find and disable, light platforming elements which are aided by casters' buffs, and the occasional mind-bending puzzle. This game goes for a different system of awarding loot and experience than others do. Experience is awarded for completing adventures or for doing optional objectives during them. Loot comes from chests, not from monsters. This game has no regenerative health. Health (and Spell Points) are instead regained by resting at shrines, which are placed at specific points in adventures. Healers are therefore always essential.
The graphics in this game are decent, better than most MMOs'. Some stuff looks blurry, especially in the encounter areas where the draw distance can't keep up with the epic scale, but overall most everything looks good. The graphics go for a somewhat realistic style. Magic looks awesome. Seeing and enemy shatter as it is flash frozen to death never gets old. The dungeon design is awesome. There are probably around 200 adventures, but you can always tell each one apart. Sound effects are good. Nothing sounds goofy, and they add well to the intensity of combat. Music is nothing special, mostly just soft creepy music that alerts you to the presence of enemies.
This game goes for an interesting microtransaction system. The cash shop has no gamebreaking stuff, and you can earn points for it by getting favor from completing adventures. Most of the good stuff lies in the content packs. Most of the game's content must be bought from the store. You can also just go for a $15 a month subscription and be able to use all the content and get extra store points. Besides the content packs, the store is mainly devoted to stuff that you could get in an in-game store. The store allows you to buy stuff in the middle of an adventure and not get the reentry penalty.
DDO has no grand overarching plot, but there is still plenty of story. With all the content packs, the game is episodic in nature. Each quest has a story behind it, and it can be interesting to read them, but it is in no way necessary to pay attention.
DDO feels more like a co-op mode for an Action RPG than a real MMO, but that doesn't stop it from being a great game. Check this one out if you're sick of the grinding and fetch quests that plague other MMOs.