The change in contrast seems fine to me. I don't think that is too extreme. Video-wise, I'd be more concerned about them grain-reducing the thing too heavily. All Quiet on the Western Front hit a good balance of grain reduction; hopefully, they'll do something like that. I'd be interested to see how the end result will compare to the current, rather nice-looking 1080i HD file on Cinemageddon; it's too bad that that one suffers from being 25fps.

Audio-wise, I'm a bit more concerned. I seem to recall, on a thread about Dracula, there was discussion that the more recent DVDs had noise-reduced sound compared to the original 1999 DVD; I hope they don't severely reduce the noise for this track. It'd be unfortunate if the HD audio track suffered from clipping.

The change of the opening "Swan Lake" caught me off guard though. If anything in the video seemed revisionist, it's that. Was the "Swan Lake" at the beginning always suffering from those speed issues? If so, I don't think that replacing it with a contemporary recording is an apt solution. There's always that small, small, small chance it could have been a deliberate distortion. They didn't make clear that the "Swan Lake" in the 1931 Spanish version was the same recording without the speed issues; it could possibly have been another recording.