I also wish that had taken off; 3d-graphics via a software ray tracing engine would in a sense be a return to the way things worked in the 90's before hardware rendering, where every game had its own custom engine and developers were always trying crazy new things. In some sense, GPU hardware has gotten flexible enough that we're sort of back in that world again, but writing GPU code isn't quite the same as writing a renderer from scratch.
When it comes to ray-tracing in particular, as far as I know there really doesn't exist (except perhaps as research prototypes) any hardware platform that's great at ray tracing. CPUs are okay but they need more parallelism. GPUs are okay but (as far as I understand it) they aren't good with lots of branches and erratic memory accesses. It seems like KNC/KNL ought to be ideal for this kind of thing (and in fact, it appears a fair bit of effort has gone into optimizing Embree for Xeon Phi).
When it comes to ray-tracing in particular, as far as I know there really doesn't exist (except perhaps as research prototypes) any hardware platform that's great at ray tracing. CPUs are okay but they need more parallelism. GPUs are okay but (as far as I understand it) they aren't good with lots of branches and erratic memory accesses. It seems like KNC/KNL ought to be ideal for this kind of thing (and in fact, it appears a fair bit of effort has gone into optimizing Embree for Xeon Phi).