If you haven't tried it yet, give original Gnome 3 / Gnome shell a go. You might like it even more than Unity. I get a feeling that by jumping straight to Unity, they will cause many people to be excited about it, not knowing they've lost something at least as good.
Unity is not bad by any stretch, but it feels unfinished to me when I use it. I kept hitting the wrong thing and breaking the flow of whatever task I was doing. I'm sure with some more experience with it I'll quit doing that, but it kept violating my expectations and stealing my attention from more important things.
Gnome 3 was a big change, but felt much tighter and polished. I didn't seem to have to think too much about how to do stuff.
Based on that experience, I think I'd like to use Gnome 3 on Ubuntu long-term.
