My complaint about Pull Requests is that they shift responsibility for doing the grudge-work from the submitter to me. As someone receiving a contribution, I have to read the contribution, make sure it merges cleanly, make sure it passes tests, etc. I'd rather say "Looks good to me" and then let the requester do all that work. (For simple cases, there is a button to automate the merge, but that doesn't run the tests.)

This, incidentally, is how code reviews work at Google. The reviewer (and owner, if you are submitting code to someone else's project) only check that the change looks good. The submitter is 100% responsible for ensuring that the change is good.

Once the reviewer says the change looks good, then the submitter gets permission in the source control system to actually submit the change. That's the feature I want from Github. I want to say "looks good, please merge" and then let them have access for one commit. (I believe gerrit works this way.) Then, the next tool I'd like is hosted unit tests and results on Github, so that the submitter can immediately see that they merged their change correctly and that the project is in a good state.

Oh well. It's probably time to go back to hosting my own repositories.