Their model is very different now, yes, but their original presentation was based on this exact concept. I would suggest looking at their history to see why they moved away from this design, and if possible, speaking with them or discussing on their mailing list the pitfalls they ran into.
I'll speak with anyone willing to help solve technical challenges associated with this model. But until someone comes up with something "damning" then I'm going to keep moving forward.
I wish you the best of luck, and I admire your ambition (and hubris) but as someone who has been working on distributed social networking (Appleseed) for over half a decade, I'll present this:
You don't always need a singular, damning situation in order to prevent a model from being implemented. Sometimes dozens of purgatorial ones are plenty.
It just takes time and dedication, the motto of any true software developer.
Using the CPU power of a device that is capable of playing video games to calculate your social graph (that is stored on that same device) is extremely powerful and well worth the time and dedication.
