Recently I came across a good example of such a service for Ruby gems: gemnasium.com/.
The point is that when you login via GitHub service imports a list of user-deployed gems, collect the list of dependencies and begins to send notifications in case of updates of the dependencies.
But I originally wanted it was not the update notification according my
projects, but the new versions are totally random projects. And would not be dependent on language development, i.e. it would be possible to follow any repository, say in their list of tags/branches.
It would be useful, for example, if you want to build a custom RPM/Deb packages with their patches — no need to constantly monitor the updates upstream.
Nobody met the similar? If not I think I will do for myself and wishing.