One of the most frustrating things about using Microsoft Office 2010 is the complete re-design of the menu system. When you have been using a product for over a decade, you get used to where things are, or should be at least. When there is a major UI revamp, it is very frustrating, time consuming, and makes it much harder to accomplish what you are trying to do. Somthing that once was a simple series of gestures turns into a orchestrated effort of clicking through different options, tearing through in app help, and Google searches.
I don't know how many times I have cursed at Office 2010 "Where is that @!#$% menu command??!!!!"
Thankfully, Microsoft has put together Office 2010 menu to ribbon reference workbooks
to correlate old Menu System commands to their current Ribbon Bar equivalents.