In the second part of his review of Office 2007, Paul Thurrott takes a closer look at some of the major changes in Microsoft's Office 2007. Here's a snip:
Some of the most popular Office 2007 applications--Word, Excel, PowerPoint, Access, and, to a lesser degree, Outlook--have been updated with the new Ribbon user interface (in Outlook, only sub-windows like Mail Message have been updated). These applications have a pleasant graphical sheen of newness about them, but the improvements are not just skin deep. Unfortunately, these new Ribbon-based applications also make the non-updated applications--and, actually, Outlook--look sad by comparison. Once you've used the Ribbon, going back to a menus and toolbars-based UI is actually pretty painful. Hopefully, the rest of the Office suite will be updated to the new UI in a future update.