As others have pointed out running it on a traditional socket would just bottleneck it so badly as to not give better price/performance anyway so the cost really doesn't matter.
AMD would need to sell the board this would be attached to and may as well solder the RAM on as well at that point. Congratulations, AMD, you've invented your own Mac without having your own OS.
Maybe some PC manufacture might decide to release something like that, but I wouldn't expect it to be a major release. It might make a nice Steambox or living room PC that replaces a console, but I don't see them investing too much into something like that. It doesn't have the volume potential to reduce the cost of making it and the higher price it will need to have to turn a profit mean that it will have low volume.