According to Spong, Sega Genesis (MegaDrive) titles will be available for the Revolution backcatalog download system. From the article: “Our long-term, trusted source told us, under terms of strick anonymity, that Sega is “on the brink of being in a position to announce exactly what it has agreed [with Nintendo]” with the 16-bit console’s first-party catalogue to lead the way. Our source was unable to shed light on the possibility of Master System, GameGear, Mega CD, 32X and, dare we say it, Saturn games featuring on Revolution, though an announcement regarding the Genesis range will be made at E3 at the latest.”
[Source: Spong via GoNintendo]