The Release Notes report shows what changesets have been submitted to one release but not another. So if a changeset is submitted in one release but then merged to another release it will not appear in the list (because the changeset is included in both releases). You can use this report to compare versions, releases or even features.
To create the Release Notes report go to the Reports view. Right-click 'Reports' or a report folder in the tree and select 'New | Report'. Select the template category 'General Report'. Select the template 'Changeset Release Notes' or 'Changeset Item Release Notes'.
After giving the report a name and description you will be asked to select the releases you want to compare and what columns to display.
Press the '...' browse button to select the release you want to report on and the release you want to compare against.
By default the report will display the changeset id and the description when listing the report. You can add further columns by selecting 'Add...'.
Press Next and Finish to create the report. You can then select it to view it in the GUI.