For one thing, the community is pretty awesome. While the official forums do occasionally degenerate into a bit of trolling and name-calling, they're also some of the most polite, friendly, and welcoming gaming boards on the internet.
The game is relatively responsible about social issues. While things like murder, war, and torture obviously take place, you can't escape this lingering notion that there's social commentary happening underneath the story. Chain mail bikinis are largely a thing of the past. And even if the occasional midriff shows up, at least we're not sporting slave outfits. The game certainly doesn't make light of mental health issues or sexual assault.
Blizzard threw open the doors to the developers, sharing Ghostcrawler and others' insights on how the game is built, balanced, and developed. The community managers engage in meaningful, high-level topics that lend insight to their community strategies. Not only is it good for the game, there's information to be learned.
So while I obviously love playing the game, I love being involved with a game whose meta-community is better than average. It's a great place to be, and I thank you all for it. But, what about you? What do you love about the game, that's not strictly the game play itself?