Remove camera and many other features. Call it a new generation. Add camera, another new generation. Great, just great.
I guess this also would mean a return to video playback capability. Knowing Apple, the sixth gen won't get an update to add that support despite probably having a capable processor. Look at the Classics, the old ones never got the new functionality despite having nearly identical hardware.
The Nano has gone far too long without a capacity doubling IMO, I'd be happy forgoing the camera if it came in 32GB.