Alrighty, here's how it goes:
http://www.retouchartists.com/pages/speedtest.html
Basically this is a download containing a Photoshop action and a test image. You load up the image, load up the action, click "Play", and see how long it takes Photoshop to do its thing. Be sure to read the readme file as well, as it contains some important Photoshop configuration steps. Post your time results here, along with some photoshop-related specs of your computer.
Time: 1:40
RAM: 2048 MB
CPU: Athlon X2 4600+