Will files created in Word X be compatible with Word 2011, and vice versa? Yes, but to make the trip from Word 2011 to Word X, you will need to be sure to save files in the .doc format, not the .docx format. Some features in Office 2004, 2008, and 2011 will not be fully supported in Word X, but document content should be preserved going between these versions.
Can I set the menus and Ribbons in Word 2011 so they're the same as those in Word 2007 for Windows? While similar in layout, the Ribbon controls in Word 2011 are not 100% identical to those in Word 2007 or 2010 for Windows. When creating the Ribbon for Office 2011, Microsoft took into account the menu bar, toolbar, and other elements of the Mac interface.
Your review says that Word 2011 matches the features of its Windows counterpart. Does that parity extend to contextual menus that appear when you're highlighting text, cutting and pasting text, formatting tables, and so on? Many of those menus will be the same or similar, but they aren't exactly the same.
Does Word 2011 support font embedding? The Windows version has done so forever. Word 2011 doesn't support font embedding.
Does Word 2011 support book-fold printing? Word 2010 for Windows does. No, that output option is not available.
Will Word be able to display and let you edit mathematical equations created in Office 2007 or 2010? Yes. Word 2011 uses the same Office equations engine used in Word 2007 and 2010. You will find options for inserting and editing equations in the Document Elements Ribbon tab.
In Word 2010, each comment is assigned a number--very useful. Does Word 2011 do that? Yes, you will see a comment number in the comment bubbles.
Can I move files from the Windows version of Word to the Mac version and visa versa? Yes. You can do so in any of the usual ways (as e-mail attachments, via shared network drives, and so on), or you can use a SharePoint site or SkyDrive to store Office files online and then access them from either platform.
I run Word 2010 and have dozens of macros. How complete is the Visual Basic for Applications (VBA) support in Word 2011? Will I have to tweak any of my macros for them to run under Word 2011? Office 2011 uses the same VBA engine as the latest version of Office for Windows. However, there are some differences; for example, ActiveX controls are not supported in Office 2011.