The next-generation N-Gage platform is available in the Nokia N95, N93, N81 and N73 devices. It takes the high-quality gaming experience that users of the original N-Gage gamedeck devices enjoyed, and allows owners of a range of S60 smartphones to easily discover, purchase, play and share those games. The new platform is distinct from that found in the original N-Gage gamedecks, and targets S60 3rd Edition phones only.
There is a thriving community at N-Gage Community
There is much more to come! check out the N-Gage FAQ
Support for N-Gage is via the Forum Nokia PRO N-Gage Zone, accessible by invitation only. The N-Gage platform SDK is not available to individual games developers.
First Generation Open source games
The game Avalanche+ was initally on the N-Gage. The source code is now available and could easily be ported to S60 mobile phones. Some work has already been done converting the sound for the game to S60 Mobile and appears to be working on Nokia 6600.