Intel refuses to say much about the part...
"...other than to describe it as a "many-core," re-programmable processor that will work as an x86-based standalone graphics product."
What more needs to be said? Intel, Sun and the GPU vendors are all heading for the same centre ground. They're just starting from different positions.
GPUs came into existence because their work is embarrasingly parallel and requires relatively little code, but GPUs are bandwidth limited and so GPU vendors are working on improving the instruction sets.
Put several dozen x86 cores onto a chip with enough internal memory to store the "firmware" and presto, you have a GPU with a sensible instruction set. Intel's experience with the 80-core chip probably convinced them they could ensure that it, too, was bandwidth limited.
Conveniently, such a beast is *also* a Niagara-style chip for server workloads. I wonder if Sun have considered putting their chips onto graphics cards?