Earlier quoted context omitted.
Private repos were a paid plan on GitHub for a long time. Actually, a lot of people used GitHub for public stuff and BitBucket for private repos, because BitBucket did offer free private repos.
Yep, I still use it this way. I believe that GitHub free for public only repo model is the reason why we have a lot of pet projects published, most of which were not really intended to be published to begin with.
Re: Ask HN: Why Did Mercurial Die?:(
#31GitHub has had unlimited free private repos for several years now. IIRC there is a limit on the number of collaborators you can add.