If I understand the article, the goal of the site is not merely to provide a toolkit for collaboration but to build a community around it - which is critical if they want to achieve adoption.

With Gitxiv, two minutes after following the link and reading the blurt, I have access to a continuous stream of projects organized in categories, to which I can post comments - in essence, it's a blog focused on CS news, which also can be used to kickstart collaboration. This already provides me with value even if I don't intend to use the platform. It's a neat approach for filtering the noise and providing a strong signal.