I think the problem is exactly as your link says; lack of professionalism. The question of "community broadband" doesn't have to imply a bunch of amateurs waiting for each other to do it, and I think Comtralis is worth a closer look, frankly. It's using a community mesh, yes; but it's offering a professional service.

As to the contention, well... we'll see. I was talking with someone who used to install switch gear for BT (he worked for Marconi) and he has a very, very good knowledge of how they manage contention.

According to him, there's substantially no difference between the way they manage contention at 50:1 and 20:1 and when the lines get busy, they'll have to re-configure their system. I found his argument pretty compelling.

But until both networks are running at full chat, it's pointless hand-waving to speculate on which will run out of steam first.

For what it's worth, my DSL service is already showing signs of heavy contention; I can no longer stream 128 kbit internet radio except off peak. Spending a little while doing streaming benchmarks shows that my DSL throughput hovers around the 350 kbit mark and frequently drops below 200K - and every now and then, gives me 60K or so.

Not sure about your point about local networking. For example, in Newmarket, the vet will be using a VPN tunnel back through the mesh from Tattersalls, to the surgery LAN. No need to go back through the Internet for that. Then there's VoIP calling locally...