not a mature technology. how would the mesh be established? run ethernet cables between people's homes? have everyone open a port on their wifi router? this is beyond the technical capability of the vast majority of people. it would require a company to coordinate this, and at that point you've got just got an ISP running the last mile anyway.
True, but neither are municipal broadband ISP's a mature organizational model. In both cases, we have a few plausible examples, but much more work is needed to verify their viability.
For my eye, I think that CJDNS is the most likely of the current candidates to emerge as useful for this sort of implementation.
