Diego said:

That's right, it's great that one of the most iconic prequel moments is finally getting the respect it deserves. I suggest the "NOOOOOOOOOOO!!" is added to Star Wars when Vader loses control of his TIE. And then to ESB when he enters the Hoth hangar and the falcon is just leaving, or after Luke jumps, or both.

Seriously this has to be George just giving us the finger.

I quite believe it is just that from a psychological point of view. People disliked the prequels. "Nooooooo!" was a rightful target for mockery of the PT and its varied, numerous faults. Lucas is butthurt by these things, which is why he drastically reduced Jar Jar's role in AOTC. He hears the fans. He listens to them. He may not do what they ask for, but he hears them.

So, adding "Noooo!" twice to that crucial scene is Lucas' way of telling fans they're his movies, he can do what he wants, and you're going to buy it anyways. I'm not saying that's his literal intention, just that it could be a subdued psychological driving factor.

Take something the fans hated in the PT and put it in the OT. Remind them that they're his movies and it's all supposed to be one saga of Darth Vader. "It's poetry, it sort of rhymes." Diminish the work of more talented directors, writers, and producers so that your fingerprint on the entire saga is clear in every scene and every frame.