Take this with a grain of salt, but an interesting little document popped up on Sega’s PR site that mentions quite a few details that the two companies are in discussion about. These include:
-PS2 emulator on PS3, the document citing games such as GTA Vice City and an unknown Sonic title.
-Consideration of import titles on PSN, menus translated. Yakuza was brought up as an example of a game.
-Sonic All Star Racing is open to DLC characters to differentiate the PS3 SKU. Not Ratchet and Clank, but others are likely.
-Sonic Anniversary is a proposed project that would put a ton of Sonic games on one blu-ray. SCEA would love exclusive power-ups and different game modes.
-Dreamcast digital title support. While not exclusive to the PSN, the proposal is Sony can pick which titles it wants more, with long exclusivity meaning more marketing support for Sega.