AFAIK the MegaDrive had very similar graphics to the Amiga as well as the CPU so it shoud be even more compatible! :-)
Not so much. The Mega Drive/Genesis VDP is based around layers of tiles and free-moving sprites, like other game consoles, rather than the Amiga's free-form bitmap approach. That said, the Amiga can do tile-based graphics almost as easily with the blitter, so if you design with that in mind, it shouldn't be that hard to go between them.
