Is it vendor lock-in if the clients want to be there? It's more like you can be in the club with the good music and hip people, or the club with the average unknown DJ and an empty dance floor.
That makes sense for GPU-compute-in-the-cloud applications where you can pick the hardware and don't care if other hardware doesn't work, but some people want to write programs that use GPGPU that can run on anyone's machine.
