Some changes discussion on mf.com

User897 said:

Changes noticed:

01. Escape pod launcher lights now have heat trails over them, making them flicker.
02. Escape pod hatch is no longer blue.
03. More moisture vaporators added.
04. Leia hologram now looks more blue and prequelish.
05. Treadwell droid behind Uncle Owen while talking at the table (Was this there before?).
06. Binary sunset still has the passing clouds added.
07. The area beneath the Landspeeder actually looks GOOD.
08. As pointed out by Adywan, there are now rocks in front of R2 in his hiding spot in the canyon.
09. If you thought the DVD version of Obi-Wan's Krayt Dragon roar was hideous, keep your thumb on the Mute button. That's right. It's WORSE now.
10. The new CG rocks that covered R2 are magically gone after he comes out of hiding.
11. 2004 detention center hallway still there and actually looks good.
12. Obi-Wan/Vader duel on Death Star lightsaber blades are bright and more consistent, though Vader's is a bit pink in some of the shots.
13. Millennium Falcon vs. Sentry TIE's, the shot that was revealed to us by LFL at the press event with the partial laser bolt IS FIXED in this MKV.
14. Brass can now be heard during X-Wing dive to the Death Star.
15. The glitch under Vader's TIE and his escorts after "Three marks at two-ten!" has been fixed.
16. Energy wave sound from Death Star explosion sounds more balanced.
17. Vader's breath sound can be heard when his TIE is spinning, but is very faint.

10 remind me of the windows in cloud city.

13 and 15 are supposed known fixes from the press event, I doubt they're fake.

Also:

Topeka said:

Another confirmed change in Return of the Jedi is a new effect when Han is unfrozen from carbonite.

Of course no screencaps yet. Grain of salt taken.