Like some of you have said 3D has been around since the 50's but it will take someone with the skill to step it up in the right direction, and if anyone can do it that person is jim.
Just think CGI was a fancy gimmick in the early 80's and no one took it seriously intell the likes of Cameron used it for T2 and Steven Spielberg used it for Jurassic Park. I know back then CGI technology was not that great because of the computing power, but it was around years before T2 was made (Willow was one of the first movies to use it) and Cameron was one of the first directors that showed how great CGI can be. If Cameron is now using 3D for his movies he will be using it because he knows its possible to get the 3D vision he has been dreaming for.