I don't think there will be more changes, but I would like that to happen. Just to fix the laser bolts and lightsabers from the 2004, and to remove the blue tint. ( the release I'm most excited will be the blu-ray of TPM. I really do hope they remove the grain.)
Those HD versions shown on cable are just upscaled versions of the DVD. The box to be released will be a saga pack, not one movie or one trilogy.
The 3D release is a completely different issue. They will be released in 2012 (not 2011 like the Blu-Rays) and each movie will be released with a break of a couple of months.
And I agree that Lucasfilm should release the OOT. I heard recently that TESB was recently included on the LoC. And I'm sure it was not the special edition. There is hope.