Compare Document Versions
This feature is so handy you'll wonder where it's been all your life. You can see the full history of a document in Nook Support Forums, and compare any two versions to see what changed between them.
When viewing a document just click on the magnifying glass icon next to the version number to see the two most recent versions compared side-by-side. Or, click on Manage versions in the Actions area to see the entire history of the document.