N-gage did live fairly long inside Symbian phones much after the N-gage phones as kind portal for mobile gaming. Nokia threw the brand totally out as they started to build OVI as the end of it all considering their services.

OVI is the place to get it all and if anything Nokia has been hard in work to simplify for long time now so bringing back N-gage imo is the last thing they should do. Maybe if/when Symbian/MeeGo have gathered nice amount of games we can start talking about OVI games. Something similar Apple has done.