I ought to knock of half a star for the total lack of acting, but Cameron was going for stereotypes, and Avatar has those under every rock.
Artwork is out of this world, which is only right because the setting is on another planet. A lot of imagination went into the scenery, the indigenous sapeints and the flora and fauna. Not so much the military gear - most of that was sci-fi boilerplate. Cinematography and CG are superb, and blend seamlessly.
Worth matinée with the 3D surcharge.