I have just upgraded to Office 2007 but find myself still using 2003 Pro.
Why? It's just that good. The layout is by far the best out of all the office products, and the menu driven system allows you to create very professional work with little input. There are even templates and wizards to help you along the way. All the major office programs are here except FrontPage, which most people wouldn't use anyway, unless into web design.
Overall, I have given it 5 stars as it is the best value for money as well as being a very complete office package.