Interesting, but this doesn't address the other problem--I fundamentally dislike Github! (I use Bitbucket because of consistently stellar support from Atlassian and an overall pleasant working experience.) And going outside my current, working ecosystem for benefits I consider dubious at best--the overwhelming majority of open-source projects get no outside commits, ever, and magic Github pixie dust doesn't really change that--isn't really a good use of time.
For me, Git and Github are both problems with this "GitHub's your resume" thing, not one or the other.
I'm sure a bucket full of your source code on bitbucket will serve the same purpose when interviewing. I'm on the job hunt and in interviewing with some YC startups we haven't really gotten to my github, since they more were interested in some of the closed-source projects I've done at other jobs. I think the overall point of the article is to be able to show people you can code rather than just list it as a bullet point in a document.
Sorry--I meant social processes. If the mindset is that "Github is your resume," then the focus is that Github is your resume, and the line of thinking goes, so to speak, "if it's not on Github, they don't have it." Which is not good.
While social networking makes sense to have a single central location makes sense (but not totally so, see G+ v. Facebook), writing code does not.
My resume is my resume. My personal code is closed-source, with the exception of a couple of bits for presentations and an archived project for which I am a maintainer. You could say that "well, that one archived project is your resume," but that would be foolish (not that you are saying that, but it does follow from all of this) because it has little to do with what I actually do.
More than anything, though, I kind of find all this "anoint the buzzwordy startup as the new X" stuff silly. Maybe one company in ten would actually follow a link to Github or Bitbucket on my resume, regardless of the content. At least for now, the resume is the new resume.
My current personal project is a cross-platform game framework for Windows, OS X, Linux, Android, iOS, 360, and WP7. It may be commercializable, and as such open-sourcing it makes little sense. If it's not, then when I'm done with it I'll likely open-source it.
This also lets git users contribute to your project, so you get the benefit of GitHub's community without having to deal with git.