Wow, Harmy, this looks fantastic. I think ROTJ was the most FUBAR of the OT 2004 transfers.
The colors look brilliant and accurate. The Sarlacc looks totally seamless, far better than I'd ever imagined would be possible! The musical number blends in surprisingly well. The Death Star 'splosion looks good. And the final scene looks seamless too; I can't even tell when it switches sources!
The only thing that I think even potentially could be improved is Anakin's eyebrows. I'm sure what I am seeing is the best possible job of recompositing them, but I point this out as the sole item of changes that is not totally seamless.
That being said, I really need to find a blu-ray player. :)