I haven't heard anything of JEJ doing the voice of Vader and am asuming that Hayden's voice tweaked appeares as Vaders voice?
Am I correct, 'cos there is absolutely no mention of JEJ so far being the voice, I dunno what my feelings are if he is or isn't the Ep III Vader voice.
Hope he is though, no more JEJ on end credits, nooooooooo

It's been known for years that JEJ did a few lines for this movie.

thank you, and goodbye

Thanks.
Na, the only reason why I brought this up was 'cos of the "Yes Master" line in the trailer which was confirmed as being Hayden.
Now skip forward to A Hero Falls and I'm 100% sure that is NOT the same "Yes Master".
I have the 5.1 DVD and the 5.1 trailer, and through that you can tell a huge difference in the voice, the first was high pitched and american sounding. The second is classic deep JEJ, anyone noticed this, cos my whole family noticed the diffeence, I admit wuthout the 5.1 it would be harder to tell. Pointless mentioning it, but nobody has stated the difference before - hope you guys don't mind

It's not a HUGE difference in the voice. They just added some reverb to it in the A Hero Falls vid.

JEJ is doing the voice of Vader.

Why wouldn't he?

Oh, and the movie does begin with "A Long Time Ago in a Galaxy Far Far Away" followed by the title and opening crawl against a starfield.

Nobody has confirmed this, but I'll bet dollars to doughnuts that it's true.