99.9% percent of companies try and do this one of two ways.
1. Use a variant of normal wifi gear that is hopped up on amps and huge antennas to form the mesh.
2. Use equipment that is actually designed for this kind of thing (motomesh and the like, and even they have issues).
Option number one ALWAYS gives you a shitty network. Option number two results in a cost per square mile that frightens the treasurers of even the most well off cities. Out of all the cities that have looked into this or tried it I've only ever heard of two that didn't crash and burn instantly.
No one will ever make a successful business out of trying this crap with just 2.4ghz equipment (and if they do they're just taking the money and running when the network turns out to suck).
and @ubuntun00b... No ones dsl or cable by itself is going to have enough bandwidth, and good luck using more than one connection on those proprietary, ISP provided modem/router/AP/voip combo boxes. Half the nodes wouldn't be able to get the built in wifi turned off and the stand-alone AP turned on. Even if they do you'll break SSL, vpn, and a whole slew of other things right out the gate.
Many smart companies have tried this planning for a good fiber pipe every other city or so and they failed...anyone adding that much load balancing on residential connections will only fail that much worse.