I for one believe that 3D will become a critical part of movies, but to say that it's future of it is folly. We are nowhere near photorealism, especially for human characters. I think a blending of live-action and 3D is really how it should go. You get the best of both worlds then, an actual actor's face and expressions, but the special effects that would have been impossible before.
I mean, when watching Lord of the Rings, I can easily tell in a scene if they're using the actual actor or just a CGI rendering of their character. That's for humans, at least. Orcs and other non-humans don't stick out so badly.