I think this would be really interesting, however I would think you need it to have a lot of customizability. ie: not all my github projects are relevant, or something I would want to marked extensively over others, so you would need a way to filter the content of the feeds.

And I do think it's important with integration to github/bitbucket etc, linkedin with more. If I am to use yet another portfolio site, I would want to do the least amount of work as possible in setting it up.

I'm very interested to see where this will be going, and wish you the best of luck. :)