Municipal networks aren't securing the link between customer and node: This is a critical failing and one I've written about briefly before. Frank Bulk writes in Network Computing about how this giant breach in basic security is just a fact of the municipal networks that are deployed and deploying. Adding a layer of security increases complexity, and Bulk notes it also reduces the choices available for a municipality to build out the network.
If consumers can figure out PPPoE or receive preconfigured PPPoE boxes, there's no good reason that CPEs for municipal networks couldn't be preconfigured to handle a WPA Enterprise login to secure that local link. Otherwise, the first Wireless Philadelphia story on launch won't be about its finances, but rather feature a TV reporter driving around the city reading people's email.