Why do you think it's beta? There is no *true release* as JDownloader is under steady development. Makes no sense for a release that is outdated at the moment it got released. JDownloader supports more than 7 thousand different services and there are multiple updates each day for new plugins/new features/bugfixes.. Don't see any advantage of a *true release*
So the build date is the most easiest to use and compare to check if a version is outdated or not. I doubt we will compile/release 2 versions at the same second