As far as I've heard, Cheese is nowhere in the game. But I expect there will be expansions, with more characters, areas, and levels (therefore nanos) added.
Today I bring you:
I didn't cap it, but several levels ago there was an incident where it appeared that Fusion Eduardo was trying to get us a message helping us learn how to beat Fuse. I don't know if the Fusion Foster's characters are really helping or if its a trick, but the Foster's characters are the only ones this has happened with so far...