I'm probably in the 5% that doesn't like what MS's done with Office 2007. I had Office 2007 for a while and then reverted back to Office 2003. Word 2007 was awesome, but Excel and PowerPoint left bad tastes in my mouth since I've been ingrained in the ways of Excel since Excel 97 and I didn't like the changes and also since I find it's a lot harder to use PPT for drawing diagrams in 2007. I also got tired of accidentally saving stuff as .pptx, .docx, or .xlsx and having people I e-mailed the documents to say they couldn't read them.
Also, I'm a guy who likes to be able to have a multiplicity of toolbars and dialog boxes in front of me at once, rather than flipping through menus (which is also why I like having 2 monitors rather than flipping back and forth between virtual desktops). If you're like me, then Office 2007 isn't for you since the Ribbon interface, although it is clean, is somewhat frustrating to use when you want more than one option in front of you (say the equation editor and the formatting toolbar).