Amazon Japan and YesAsia have now both added the tracklist (partially) for the Sonic Generations OST to the item descriptions.
The tracklist is as follows:
2. Green Hill Zone – Classic
3. Green Hill Zone – Modern / Normal
4. Green Hill Zone – Modern / High-Speed
5. Chemical Plant Zone – Classic
6. Chemical Plant Zone – Modern
7. Sky Sanctuary Zone – Classic
8. Sky Sanctuary Zone – Modern / Normal
9. Sky Sanctuary Zone – Modern / High-Speed
1. Mushroom Hill Zone – Classic
2. Mushroom Hill Zone – Modern
1. Stardust Speedway
2. Round Clear
It appears only the classic-era tracks are revealed. It seems Disc 1 will get all console tracks on it, and Disc 2 will be dedicated to the 3DS tunes. It’s not clear what tracks exactly will be on the 3rd disc though.
The Sonic Generations OST: Blue Blur is set to release at January 11, 2012.