Al,
Unlike Bert, I'm a little more daring w/ new OS's. So, I upgraded my whole office to Vista Business edition. Through the MicroSoft Partner program, I was able to obtain discounted software rates. I also have Office 2007, Enterprise Ed., which has all the fun Office programs and some others I haven't used much. One cool little program is Office OneNote, which allows you to save "sticky notes" to yourself.
However as Bert replied, I'm a Latest and Greatest type of person, w/ the caveat that not all latest things are what they are hyped up to be.