Revision numbers are not really what is important to know what version you use. (Some packagers left it in as a reminder of a past before git.)
The git hash is what really identifies your version. This is the stuff after the point in your revision number and also the stuff after -g in the version string. You can then use git log on the source repo to really see in detail where your nightly build is along the development and what changed recently (or even after it)
obligatory: Is it a good idea to use a nightly build version?