A Mario game on the ipod would be really cool, but at the same time difficult. controls would be hard to do and it doesn't really seem to me that it belongs on the ipod/iphone
The Toki Tori platformer on the iPhone is <10mb with a lot of content as well. If the games take up more space then it is usually not because of sloppy programming but due to the size of the graphical textures and audio.
Controls aren't that hard, we have options for tilt/on-screen buttons, virtual d-pad, touch sides of screen/gesture based.
Nintendo offering Apple (Gameloft, anyone) rights to the title of "Mario" on the iphone, think it'll happen? Never
Sonic = Sega Sega hasn't had a platform for years. It can develop games for any platform it wants since thats the only way it can actually make money. Whereas Nintendo has it's own gaming console and makes millions of dollars and has no need for developing on other consoles/devices other than it's own. And seeing as to how Apple keeps bashing it and saying how much better a gaming device it's iDevices are, I doubt Nintendo would even consider making a game for the iDevice and give Apple yet another reason to be the smug and arrogant bastards they already are. No offense to Apple, I love Apple made products.
I've played so much Mario in my life that I really don't yearn to play it very often. I have Super Mario Galaxy if I need it, emulators that play SNES and N64 games. So much Mario...