3D was a real addition to the experience of the movie. Great depth and realism.
CG was definitely taken to a new level. CG was 99% realistic. Scenery was incredibly real, CG-only scenes were smooth. The flora and fauna of Pandora were imaginative and believable. Action scenes were exciting.
The "meh":
The movie was 3D, but the storyline was 2D -- predictable and not extremely satisfying; just passable.
Obvious Native American parallel was just a bit too "in your face".
Ending didn't satisfy. What happens if the Earth folks come back with a huge armada?
Overall, a really good movie that pushed CG to a level that finally makes it seem like a viable replacement for "reality"... That seems like an oxymoron...