I am not sure what needs that blazing speed anyway. I was watching video on a 266MZ Pentium 2 machine with a video accelerator card. (my first DVD player).
A 2mz P4 seems to do just fine on most things and once you get up to 3mz I am not sure what the average person can't do.
I suppose if you are into gaming big time or doing video editing it is useful but certainly not for the things I do every day.
Of course if you load it up with a bloated operating system that eats CPU cycles for the sake of eating them you need a new machine. They just have not showed me what 7 and 8 can do for me.