Nintendo should swallow their pride and stop making consoles and stick to a) making handheld units and b) making software for both Xbox and PS. Sega bit the bullet and did it because it made sense.
Really? Try this:
MS should swallow their aspirations for world domination and stop making consoles and stick to a) making OSes and office suites and b) having Bungie, Rare, and whatever other development houses they own release their games on PS2/3.
Sounds a bit absurd? Actually it doesn't to me. MS pissed away ~2 billion ("where I'm from that's a lot of money" - Fitch) for "a chance to play again", as they put it. IF by the time this upcoming generation is over (I assume around 2011-2012) they can make up their loses, then they'll be right where they were 10 years earlier.
Why would Nintendo stop making consoles? Because you want to play their games on whatever system you have? I'd love to be able to play all the MGS games on my Gamecube, too.
Sorry, but I don't see Nintendo bailing out of the console business anytime soon. Doing that made sense for Sega because they were really at the end of their rope. It took like 4 or 5 failed systems to get them there. Last time I checked, Nintendo, a game-only company, had 3.5 times (please correct me if I'm wrong here) more $$ in the bank than Sony the "electronics giant".