[update] Seems like some sources have changed or the lack of sleep really got to me. The game is NOT teased as ‘Nintendo developed’ but as being on a ‘Nintendo platform’. 95% sure this will be the Sonic 3DS game. [/update]
Nintendo fans have been complaining that HD users are getting Sonic Generation, but those Nintendo only users might have their own exclusive title to look forward to!
According to Eurogamer Portugal, the next issue of Nintendo Power (the E3 edition) is going to reveal a new Sonic game exclusively for a Nintendo platform.