Wow, I don't know what OS this guy is talking about or what FAKE benchmark he is using.
Vista was and Is since SP1 faster the XP on anything but the "benchmarks". It multitasks smoother for people using heavy amounts of computing, say a few copies of LINUX. Benchmarks are nearly useless at this point in the PC evalution.
Win7 handles 8 cpus like it was made for it, well I guess it was, and will never be unresponsive to the user, that is my experience with XP and WIN7 on very heavy loads to the tune of 64 threads and all 8 cores at 100%, still baby smooth, XP will not be smooth if you use more the 80% cpu, it just wasn't written to handle it!