PyPy core dev speaking here. I do it mostly for passion. Every now and then I have to do something for someone that falls into few categories like "stupid website that would never take off" or "some pypy usage that makes absolutely no sense to the broader community". Those things mostly slow down pypy development and frankly the benefits are very very low. I would be more than happy to get rid of this stuff as it's distracting. Can gittip be the way to do it? Maybe. Would it be beneficial if we find some way to do it? I think so.