I just approved hammerd's post above, a few good tidbits in there, especially the "20% hardware addition" which is much more precise than anything else I've heard out of them (even if it's not very meaningful without an idea of what graphics core they're pairing it with).
I talked to the ex-CTO of Caustic at MWC11 a fair bit, I wanted to post/publish something based on it, unfortunately my memory is significantly worse than that of the average goldfish (which doesn't have as bad a memory as you'd think but still) so combined with the ridiculous amount of discussions I had every day back there, I honestly can't remember some important details so I didn't feel confident publishing anything. He did mention the basic 'magic' behind it is detailed in a publicly available patent though (which I haven't had the time to properly read sadly).
Anyhow, Caustic 1 is based on FPGAs and that's still what they were demoing at MWC11, but they were still working on the 90nm Caustic 2 chip - I can't remember if it had already taped-out at MWC11 or was about to tape-out sadly, but iirc it did not tape-out before the IMG acquisition.
The short-term end-product will be 90nm Caustic 2-based boards for the workstation market which people will pair with NV/AMD workstation GPUs, the mid-term end-product is a similar piece of IP that will ready to integrate next to Rogue, and the (very-)long-term end-product is something that shares some silicon between the two - he mentioned there was some similarity between the TBDR logic and their own algorithms interestingly enough, so you wouldn't have a bit less rasterisation hardware idle when raytracing and vice-versa. I'm not sure if there's that much to gain there, but it's a possibility they're considering (many years down the road, depending on RTX success, etc).
One technical bit I remember is he was very confident they could scale performance as much as they claim in the future without becoming bandwidth limited - their bandwidth cost is low, and if necessary there are a few things they can do to reduce it further (but increasing silicon cost and there may be efficiency trade-offs for some of them). So basically you'd expect non-raytracing related bandwidth costs to remain the majority of the total GPU bandwidth. On the other hand, PCI-Express bandwidth can be a real problem, so they won't be able to scale discrete solutions much further than Caustic 2.
And tangey, they won't need 4-5 years to have it suitable for SoC integration - there's nothing magical about that, Rogue looks just like a NVIDIA GPU to them except it's on the same chip. Whether that means it will actually get implemented soon is another question, and it also remains to be seen what markets it will target first.
Besides handhelds (which might be hardest to penetrate), you've got consoles, set-top boxes (he specifically mentioned some big players might want to create a gaming ecosystem around it and use RTX as a differentiator - Apple TV? Samsung?), and workstations (since discrete solutions will be limited by PCI-E). The problem with workstations is how do you find a partner to make a many-core Rogue+RTX chip with performance comparable to NVIDIA's Fermi or Kepler? And to make that profitable you probably need to target the PC market at the same time.
I think it's pretty clear they didn't have a partner for PC/workstation yet but at least with Rogue (and RTX) they can scale up to NV/AMD-level performance, so they must logically again be actively looking for potential partners there (unlike in the SGX generation). Who knows if anything will come out of it or if it'll be another crushed dream like PMX590.
