There's a positive, in-depth (pardon pun) by Manohla Dargis in the NYT. More important than the 3-D was the other technology:
"Mr. Cameron has said that he started thinking about the alien universe that became Pandora and its galactic environs in "Avatar" back in the 1970s. He wrote a treatment in 1996, but the technologies he needed to turn his ideas into images didn't exist until recently. New digital technologies gave him the necessary tools, including performance capture, which translates an actor's physical movements into a computer-generated image (CGI).
... In keeping with his maximalist tendencies, Mr. Cameron has shot "Avatar" in 3-D ... an experiment that serves his material beautifully. This isn't the 3-D of the 1950s or even contemporary films, those flicks that try to give you a virtual poke in the eye with flying spears. Rather Mr. Cameron uses 3-D to amplify the immersive experience of spectacle cinema. ...
After a few minutes the novelty of people and objects hovering above the row in front of you wears off, and you tend not to notice the 3-D, which speaks to the subtlety of its use and potential future applications. Mr. Cameron might like to play with high-tech gadgets, but he's an old-fashioned filmmaker at heart, and he wants us to get as lost in his fictional paradise as Jake eventually does.
... one of the pleasures of the movies is that they transport us, as Neytiri does with Jake, into imaginary realms, into Eden and over the rainbow to Oz.
If the story of a paradise found and potentially lost feels resonant, it's because "Avatar" is as much about our Earth as the universe that Mr. Cameron has invented. But the movie's truer meaning is in the audacity of its filmmaking.
... Movies rarely carry us away, few even try. They entertain and instruct and sometimes enlighten. Some attempt to overwhelm us, but their efforts are usually a matter of volume. What's often missing is awe, something Mr. Cameron has, after an absence from Hollywood, returned to the screen with a vengeance. He hasn't changed cinema, but with blue people and pink blooms he has confirmed its wonder."
http://movies.nytimes.com/2009/12/18/movies/18avatar.html Maybe it's because I'm a Londoner - that I moved to Nice.
Anything by Ridley Scott needs to be seen in a theater.
The scenic shots of New Zealand in Lord of the Rings were stunning and some of the special effects shots were nice. The rest, i.e., most, of the films ... not really.
POTENTIAL SPOILER FOLLOWS
One aspect of Avatar, if my Informed Sources are correct ;-), I find intriguing is the film's use of the Yggdrasil motif. It was used in The Fountain but in such a disconnected way, and it's so unfamiliar with modern audiences, I doubt it came across.
Shades of: Tapio You can't be me, I'm taken
....this I am looking forward ro.... "Any economic unit can emit money. The serious problem is to get it accepted" Hyman Minsky