i would say The Legend of Zelda. Really its the only Nintendo franchise (until Xenoblade and their purchase of Bayonetta) that i like and i have always hated that it was Nintendo exclusive because it being on PS3 or even 360 would be so much better in literally every way. I have high high hopes that whenever an NEW LoZ game is finally announced for WiiU, it will be BAD ASS.
Left for Dead deserves an honorable mention. I have played the hell out of it but always wished it would make its way to PS3 because im too cheap to get an XBL account :)