If you're intent on doing any 3D work, that area is for now, in practice if not in theory, Nvidia-only.
Are you talking about nvidia 3Dvision rather than 3D applications like 3DSMax/Rhino/Maya etc?
We find that AMD's performance and stability in those applications (on consumer cards - we have several 7850s and 7970s) is better than the performance and stability of the 560Ti cards that we have in the Conference PCs and it was better than a GTX680 that we borrowed before making the decision to stack the renderfarm with 7970s.
I think he means the integrated Nvidia 3d engine in CS6 AE which is still only accelerated using CUDA processing (at least last time I checked) . Once you turn up the ray instances, or whatever they call them, it drags your render down incredibly unless you can enable CUDA acceleration.
CS7 AE may be a different story because of the 4d lite they've integrated but I haven't seen anything specific about support for OpenCL in regards to this feature and the old engine will still have to be included to provide backwards compatibility.
Ultimately it comes down to your workload and in general CPU+RAM is probably a sounder investment most of the time. Its still largely useless in CS6 PP and AE unless your task is either fairly specific (as in the Nvidia Optiplex stuff) or ultimately rendered rather efficiently on the CPU. In general, if I was buying right now and intending to use Adobe CC (or whatever they've called Master Collection) I would get a mid range Nvidia card and if I wanted to splurge maybe one with larger than stock ram. Who knows? Maybe down the line they'll figure out how to make full use of it.
It all comes down to what task you intend to throw at it, YMMV.