I have a CUDA card for video editing (a Quadro). Bloody lovely it is as well, but the cost and the lack of support are maddening. It's like having a Ferrari and then only being able to drive it around town at 30mph.
Thing is the architecture needs to become widespread and cheaper. The benefits are obvious on software that can take advantage. But even among flashy Adobe software, only Premiere really takes advantage and even then its only a set amount of tools.
I've just downloaded CS6 from Adobe so I'm hoping there might be a slight improvement.