@hfric: Yeah, I forgot to mention a lot more things. Like that you can choose followers that help you and such.
Blizzard will certainly release one or more expansions for this game. Or they will change the game like they did with Diablo II patch v1.10. I'm now playing in Hell difficulty with my level 60 character in act 3. There's still the Inferno difficulty, so the game is badly out of balance at the moment.
The levels are too short, so it's very boring indeed to go through all of it again and again. Act 4 is the shortest of them all, you can't call that an act.
But hey, at least the server drops are solved now. I guess too many people were disappointed
That something is popular doesn't mean that it's good, but then again it's all a matter of taste. I'm sure most people bought Diablo III because of part II. I did.