It is sort of a shame about the standard client fading into oblivion, but it is still the client pushed to new and casual users. I think most people started folding with the standard client - I know I did. So, in that respect, it serves it's purpose. It's also very stable and is the client I would choose if I wanted to borg something I'm not going to see again e.g. a computer in a popular retail store.
In terms of raw power though, the standard client can't be contributing much. 88% of the total FLOPS is done by the GPUs/PS3s. Of the remaining 12% I wouldn't like to guess what the split is between SMP/standard, but you get the idea.
This is the way things are going though; multicore. Modern GPUs have a lot of untapped power tied up in their multiple processing element design which is just starting to be unlocked. We're a bit ahead of the curve at the moment. In the industry IBM are selling Cell-equipped servers and I think I heard the next version of Photoshop supports GPU acceleration. On the consumer side, Apple are integrating OpenCL into their next operating system, which is going to provide an interface for suitable applications to tap into the GPU power. This, combined with their notorious control over the hardware, is going to lead to some very "interesting" performance statistics (after their marketing department get on it at least.) Linux won't be far behind although the jury is out on Windows, because at the moment it does not like multi threaded processing at all. Roll on Windows 7.
With this in mind it's no surprise that AMD acquired ATI and Intel are making more aggressive moves in the graphics department. They know as well as anyone where the future lies. In a few years time, the term "graphics card" may even become archaic. Instead, we'll all be buying "accelerator cards" which will improve a lot of computing tasks. The General Purpose CPU is not going away for a long, long time, but the direction is changing.