This is of course a nice approach to the downside of facebook. I agree that someone else tracking by log is not ideal. How many of us only log onto the "trusted" networks with status.net service such as the old tllts status.net cloud? The techs there are far superior to many of us normal users and there were numerous problems getting access to the service even outside of many total outages. I would certainly rather have my posts scattered across many hosts rather than something central like facebook. That does obfuscate the logs and make it harder to gather all the users data easily.  Even then, though, the isps would still have logs of the interconnected traffic. My point is this sytem would make more difficult what is very easy for google and facebook and twitter, but it still does not make coallating user usage impossible. This idea reminds me of TOR. TOR does not completely anonymize anyone, it just makes it really difficult to connect one endpoint to another for the purposes of prosecution or otherwise. A lot of people think they are fully anonymized with TOR, but I've not heard any TOR engineer claim that.
Also, let's say that anyone running their own social network peer wants to have advertising on their freedom box. To advertise the owner would need to share the log info with the ad company. Then we're back to spying included for free, or at least spying for free to the owner of the box. Nothing is free for the advertiser of course.  Yes it would take a while to build the database, but that just translates to more cost to the advertiser. I'm not arguing against doing this. I just want to point out that this just commutes the problem, it doesn't really solve the problem. I'll be the first to buy a freedom box, but I won't delude myself into thinking "gee when everyone does this, we'll be truly free at last". Look into it. It's cool. It's free software. It's fun. It's awesome. In the voice of Jim Carey "I like it a lot". 