It’s cool, but just the first story arc - about equivalent to say Act 1 through Blood Raven in D2, maybe. All of the classes are playable, and you can re-play with the monsters leveling up (at least a bit, hard to tell since you can’t see levels).
I have not tried multiplayer much - we should see if we can get an SDMB multiplayer session going.
So I guess I’m not that lucky, but I’m still thrilled. I didn’t get a chance to play it last night - damn downloader was slow and it was 4+ gb, so tonight’s the night. Here goes!