Hey folks:
Not sure if anyone else caught this, but some folks at Millenniumfalcon.com made some comparison images based on a few new stills released on the new Blu-Ray official site (http://www.starwars.com/movies/saga/).
The comparison thread is here: http://www.millenniumfalcon.com/phpbb/viewtopic.php?p=165608#165608
It looks to me that some of the crushed blacks have been improved. The Jedi shot looks brighter, but not in a way suggesting someone just artificially pumped up the levels from the 2004 source. The detail that would have been blown out by the crushed blacks (like stars, some of the detail in the Death Star) look like it's there again. Could just be that the final transfer to 480p in 2004 removed a lot of this and was further darkened, and this is the "real" way the 2004 transfer was meant to look.
Also, if you compare the twin sunset shot with the comparison images on these forums, it appears to have the same colour cast, but it's not nearly as dark.
Cautiously hopeful that the transfer will be a bit nicer.