The big deal about GitHub is that they were in large part responsible for the current Open Source Renaissance we currently find ourselves in. Do you remember the world before? Where you would hunt for someone's private SVN repo on their personal site and email them patches, only to hope that something comes of your effort? Compare that with the world of today, where, if I'm using GitHub, I can submit a fix to a project I happen upon entirely from my web browser, if I wish. The maintainer is notified immediately, we can have a line-by-line discussion about the change, and then it can be merged - also entirely from the browser, if that's what you're into.

Introducing DVCS and the pull request model to the wider development world is the reason that the pace of OS software development has accelerated so much in the past half decade. Of course, GitHub did not invent git, but they made it easy to host your repositories, and once Rails migrated to GitHub, the rest of the Ruby world came with it - followed shortly thereafter by a sizable chunk of the wider web development community. If you use one of their many competitors, that's fine - but they wouldn't exist had it not been for GitHub. Remember that Bitbucket started out as a GitHub clone for Mercurial. Gitlab is unashamedly an OS clone of GitHub.

> More holes than a sieve with their Rails setup.

This is just unnecessary FUD. The GitHub and Rails teams have both been fast to deal with security issues as they are raised. Just because a security issue is well publicized, it does not mean that every other piece of software ever written does not have its own security issues.