The character development, story and special effects worked very well together and kept me from ever being bored. Ashamed to admit it, but I've already seen the movie twice; once in 2D and a second time in 3D. I hardly ever watch movies even a second time, but I will go back for a third round in IMAX 3D.
The first time I ever witnessed a standing ovation after a film was the original Rocky. The only other time was last night after Avatar. So many 5 star reviews... looks like a big hit for Cameron!