We ended up using buying a stack of them for rendering, but in the end it made more sense to buy octocore Xeons for our workload. The titans ended up doing computational tasks around CFD and such - were cheap for that. These Titan-X just seem like gaming cards only.
Actually I'm with you on that, I'm still more in favour of CPU rendering generally because of memory limitations & the fact that CPU renderers are just better featured & more mature.
But some peeps who do mostly product vis or motion graphics, GPU rendering can be a good solution.
GPU rendering most interests me for preview purposes - I want to be able to use the same materials for final render with cpu as I have been previewing with GPU. In that respect, VRay RT interests me the most.
Agree that for non-rendering compute tasks the new titan-X is no good but if you'll be doing GPU rendering with them, that 12GB of VRAM is literally double any previous CUDA card outside Quaddro range. It'll be a game changer for a certain subset of CG artists.