WCG has nothing to do with what app any project decides to use. That must come from the project scientists. The HCC app was originally a CPU app but some people associated with the original project were able to port it to GPUs. The GPUs took what would have been 5+ years of work and finished it in a few months. I was just in the right place at the right time to take advantage of it. Why any of the projects that have started since HCC ended have not been ported to GPUs I have no idea. Seems like a no brainer to me but maybe the porting process is not as easy for these newer projects. Keep hearing rumors that a new Help Fight Childhood Cancer project is in the wings but have heard nothing about whether it will GPU compatible or not. One can only hope. Even if it happens I sold off all my 7970s and could never put up the outrageous (for WCG) numbers I did with the HCC project.