Truthfully, I see the future having two components:
1. OEM'ed music systems that come from the factory pre-installed into the car.
2. Ipod or at least aux-in interfaces for factory and aftermarket stereos.
I don't think any amount of petitioning Sigmatel or anyone else is going to change the market from moving in that direction.
To answer the OP's question about the community: The community is still going strong. The existing owners of the players are still doing stuff with them. You can still buy them used.