Following the harrowing rumors on the nauseating changes in the Blu-ray edition of Star Wars, a Lucasfilm spokesman has confirmed our worst fear: the changes are indeed completely real. Check the video to see the worst offender: Darth Vader screaming No!.
I understand what Lucas is trying to do here, and at the risk of commenters doing the blog equivalent of setting me in front of a firing squad, I'm going to go out on a limb and say this would have been a good addition, if the prequels had been better.
Lucas is trying to link Anakin's loss of Padme at the end of Revenge of the Sith with the imminent loss of his son. Like in episode three, Anakin is watching his family being torn away by the forces of Palpatine and Anakin's allegiance to the dark side. When Padme died, Anakin believed he'd done it, strangling her in his rage and jealousy. In Return of the Jedi, he's witnessing the same thing happening to Luke, only with his master, the Emperor, doing the honors.
By yelling "Nooo...!" Vader is proclaiming the link between the two scenes.
I said "if the prequels had been better". The problem here is that the scene Lucas is linking with RotJ is almost universally hated. Vader is supposed to be imposing, scary, and powerful. Imagine if that scene had ended, instead of with a whining cyborg, with a cold, furious Vader striding from the room, gaining confidence on his new legs with each step, warping the bulkhead walls as he passed, then finally venting his anger by blowing the medical bay's doors out as he exited.
Now that would have been a scene worthy of calling into memory during the series crescendo.
Instead, he's soiling the classic with the dirt of the prequels. If Vader's awakening scene in episode three had been effective, then this change would have had powerful resonance, tying the two trilogies with an effective emotional hook.