I just ran across a great blog entry by John Porcaro, a Microsoft Group Marketing Manager. He has some great ideas about writing your performance review - specifically the self-review. His key points and advice should make anyone who participates in a formal review process want to click on over and get his recommendations.
His article contains the details, but the outline of his advice is:
Employee reviews can be (and when done well, are) a very useful tool, and present a real and valuable structured opportunity to learn what the next stage of growth is in our careers. It's important to place a level of import on your part of the review process that shows how important your career is to you, especially if you want others to take your career as seriously as you do.