Recently, there has been some interesting development in realtime raytracing:

• Some realtime demo started to emerge.
• Lot of important companies and people gave their opinion (including NVidia, Intel, Carmack, etc...).

I think neither current GPU or CPU are going to take over each other: GPU have impressive processing raw speed but poor cache/branching management while CPU is the opposite. CPU and GPU should simply converge, and we're likely to end-up having something in the middle to get the best of both world.

As it is really new, there is lot of research going on now. Being very interested in research myself (really considering doing a PhD now), I started a realtime raytracer project, so here we go, newest of the Entropia family is Entropia.RT... not very original, I know (sorry, I have to put Entropia.NET on old for a little while).

I have a few ideas that I would like to try and explore, especially about coherent ray packets tracing and trying to maximize use of soon-to-come 16-way SIMD. If they prove to be efficient I will post more info on it very soon.