It's actually not such a wild idea OP. I've thought of this myself. I think what Nokia is planning to do with MeeGo/Symbian^4 is make the two OSes almost indistinguishable. Same apps and games will run on both and the UI will also be similar I suppose.

From the Symbian^3 N8 videos I've seen online, it looks to be an amazingly fast phone UI. The biggest thing you would miss from Maemo would be the excellent browser. I'm quite looking forward to seeing the new Qt Webkit browser the Symbian^3 N8 will get in November as well.