I use Microsoft Word 2007 (and PowerPoint for that matter) a lot in my day job, and I think I've got a pretty good handle on where things are now since the invention of the Ribbon. However, there are still times where I think:
Now, where the %"@#'$ has that menu option moved to...
Here is a little application where you find the feature you want in a mock up of the Word 2003 interface and it'll show you where it is now in Word 2007, awesome.
I don't know how long this has been available, but I hope it'll save you some time and frustration when trying to find those missing or moved Word features.