I use CS4 not because of the wow factors, but because of the many improvements to the program, it is now more highly suited to photographers, it now runs much more faster and efficiantly, also there is the added bonus of the content aware scalling process, it really can be a godsend when resizing images and keeping a good aspect ratio, there is also a good benefit in the newly designed interface, which puts old imroved favourite tools in thier own special areas so that one does not need to go searching for things like levels curves and such like, it's vastly inproved in the new CS4 version, it is all integrated into a better and more efficient workflow...The new adjustment layers window is a great time saver.

It takes one tree to make a billion matchsticks, but one match to burn a billion trees