Finally saw this tonight in a superb quality XD theater with RealD. I went strictly to check out the effectiveness of the 3D conversion.
I have no criticisms for the PQ that I didn't always have. Those image shortcomings are still quite terrible. That said, the 3D effect was quite impressive; far better than I expected. This clearly is designed to look realistic rather than like a gimmick. There is quite a sophisticated and successful attempt to honor the appropriate depth for a given lens/focal length and proximity of the subject to the camera. Overs (over the shoulders), and close overs were particularly realistic. I dropped my glasses at times to take a look. On these closeups, there is really no 3D processing of the face; it is left sharp, but with the glasses the depth is there in the bg. Well done "realistic" 3D.
Enduring the movie was brutal except for occasional brilliance...like the final light sabre duel.
I haven't watched the movie in its entirety in many years. Interestingly, I was able to follow the convoluted political environment better this time around. It seemed a little too familiar sounding. Trade Federation squables with and defies the Republic, then places trade blockade to strongarm the Republic. One can imagine Iran in the role of the Trade Federation, the UN as the Republic, and the Straits of Hormuz as the blockade point.

IF they do more of the SW saga, Empire has the best chance to really impress due to the quality of the original images/photography. IT MUST, though, be a 4K scan, distribution and projection. That might be quite spectacular for the Hoth battle alone.
The Spiderman 3D trailer looked terrific. I think that these new movies shot 4K or better with the RED 3D rig are going to be very impressive.