Both systems were great and had a lot of gems on them but I have to give the slight edge to Nintendo for having slightly more gems on their system. I love love LOVE Sonic but I can't in good conscience put it above Yoshi's Island, Super Mario World, Super Mario RPG, DKC (especially 2), Uniracers, Tetris Attack, FF6 and so forth. Also had the better sound system. LOVE me some Genesis music but when you YouTube games that were released on both consoles and compare the music on them... that's when the SNES truly is what Genesisn't.

As an aside does anyone else remember when this console war was SERIOUS BUSINESS to us kids?

EDIT: Oh is this more than SNES/Genesis? It's Nintendo vs. Sega as companies? That's tougher; still gotta go with Nintendo I think.