The best way to review your work before you commit it, is to compare your version of a file with the last revision you got from the repository. Subversion always stores the BASE revision of files on your hard disk. So to just review your changes since the last update, you don’t even need access to your repository. This makes comparing local changes fast and convenient.
Versions offers a couple of handy ways to quickly compare different versions of the same file. Most of these functions are found in the toolbar, some are only present in the “Action” menu but can be added to the toolbar when you customize it.