Games that will easily go on forever are Mario & Zelda as long as Nintendo is in business.
Games I would like to see go on forever although I'm very skeptical of quality falling off for anything
that goes on that long are:
Resident Evil (w/ the new RE4 style action - made this stale series refreshing for me)
Final Fantasy (with new characters, new adventures, this one is the most future proof for me and has the ability to never become stale. Of course their can still be a few bad games in the series if you dont like the new story, battle system or characters. This one has the most potential of all my top 5 as long as Square Enix stays in business.
And Metal Gear Solid (but only if Hideo Kojima was on board. Once he is gone, it won't be the same without him and I don't think I'd want this series to continue. I'm actually happy with this ending with part 4. It made the list b/c of course I would love to get more games in an ideal world where all the voice actors and developers live forever also. David Hayter is Snake period.)
God of War also. (love those games... but who knows. Ask me again after God of War 13)
Oh and can't forget Uncharted. Thats definitely my favorite new game franchise. I suspect we'll at least get 2 more from Naughty Dog.
