For openSuSe, their open build service is awesome. You can create packages in your personal repos and submit to the official repo in one click. Though zypper (suse package manager) download packages serially and takes a lot of time during upgrades.
OBS can also build packages for many other distributions (including Debian derivatives) and automatically maintain repositories for them, and even supports using one universal RPM spec file to produce both debs and rpms (and some other formats) if you want it.
So you won't have to change distributions to take advantage of it. Really wish the service was more widely known.
