I'm unsure how I feel about this feature. It's one thing to facilitate encrypted data passing, or to selectively choose what data to mirror, but do I really want to serve as a host for CP unknowingly? I guess it might be possible to block known unsavory content, but that just seems like an endless game of cat and mouse.
While I like the idea of making the web redundant, I don't think it should be a feature of the web itself. People should explicitly opt into mirroring content they think is important. Anonymity is way more important than resilience.
If Freenet can succeed in helping to defeat centralized power over the web, that would be a great thing. I just hope it doesn't end up being a distraction that works against that goal. I2P has been the beat solution for a long time, yet projects with serious inherent flaws like Tor and the old Freenet suck the oxygen out of the room.