there is openCL on the ati cards, but no1 has updated the folding clients for it since they (ati, via that only use openCL) dont pay to subsidize software, there are real shader based transcoders that work on both and ati is faster now at it when comparing a 260 to a 4770. i would expect openCL to take over now that NV supports it and the spec is finalized and can work on the x86 and gpu

ive also seen more use for the cell than the gpgpu since the cell is cheap and it can do more kinds of workloads u need nested fractals for the gpgpu stuff right now to get an advantage so there are limitations