The biggest problem I've come across on Github is actually getting in touch with the prior maintainer. If the user disables issues on the repo, doesn't list their email nor their github username doesn't match up with something like twitter it becomes impossible to get in touch with them.
There's been 3 repos I've attempted to take over that had no one working on them for +6 months and this was exactly what happened.
Maybe a maintainer can mark a repo as orphaned and others can bid to adopt it using their karma? Then the maintainer has a list of people to talk to about the future of the project... just helping make that transition easy would be nice.
A simple project setting that says "Advertise as orphan" would suffice. Then a banner would appear on the page saying "This project is looking for a maintainer!" and have something akin to an apply button where you might add a short comment about your interest.
With the "Login with GitHub" feature now available, this could even be a third-party service.
It might be an interesting satellite project. One that doesn't require maintainer consent; start with statistics and highlighting, mention which projects have changed their descriptions and readmes, show contributor lists.
(github network graphs would be helpful for this if their performance was remotely acceptable)
Not necessarily. Every commit contains something that looks like an email address, but there's nothing guaranteeing that they used a real email address, let alone one they actually check.
I'd suggest that when merging a commit, checking that the email is actually valid by talking to the person concerned is probably a good idea, maybe even when they're submitting the commit through GitHub.
I've had the same problem and have an oddly related problem. I have a really good contributor to one of my projects. The only way I can get in touch with him is via github issues. There's nothing in his profile that'll let me get contact him, or even google him.
You don't have to log your commits with a real address... I use a user+github at gmail address, but others don't. It would be nice to see people list at least a twitter account and maybe a homepage. For really high profile people/projects, I can see the option to be more private about contacts outside github... but for the most part, don't get it.
There's been 3 repos I've attempted to take over that had no one working on them for +6 months and this was exactly what happened.