Neato! What Can I Do with This? Here is a list of some of the things that you can do with WP Install: http://ping.fm/GTh55
+ Install a theme including premium themes with just a click
+ Install plugins including premium plugins with just a click
+ Install pages that are fully editable with just a click
+ Install Privacy, Terms of Service and Disclaimer pages that are auto filled in and are automatically placed in the sites footer in just one click
+ Delete standard WordPress defaults in one click

Actually that seems like a lot of clicks, but some of the actions are done in the same click. I have used and seen other software that try to automate this kind of stuff, but they just didn't cut the mustard.
It is probably best for me to show you how it all works in a video: http://ping.fm/rML5k