I've had a few dungeon runs with unfamiliar people, and the whole experience wasn't that different from instances in World of Warcraft, Everquest, Guild Wars, etc. No one had enough time to listen to what the NPCs or the DM have to say, no one bothered with commenting on the surroundings or examining them, it was just about killing everything as fast as possible. Perhaps that depends heavily on the party.
While the mechanics supposedly don't reward mindless slaughter, there were several quests involving killing a certain number of particular monsters. It's impossible to sneak by some monsters and take the chest, because the chest will be artificially locked. I got the overall impression that avoiding combat isn't really encouraged at all. On the overall, while it's still an improvement over standard Everquest-clone combat, it isn't that great of a leap.
Love the emphasis on non-standard potions though.