Maybe I can sum it all up in a nice little package
The Business end (NTL/BT etc) have 'something' in place that works, for a home customer they are not going to dig up roads and lay fibre so people can have 2mbit each way (or faster of course) when the return will not make them a profit. A Business (company with lots of dosh) is prepeared to pay £XXX for a line that is fast enough for there needs, such as Leased Line from BT etc. In that case BT will happily Lay Line that only they have access too thus no bandwidth problems and also comes with it terms of service, by which i mean fixed the second it goes down (in theory anyhow).
Now the customer (me, you and a man named bob) want the following:
A Fast line, the faster the better, 10mbit both way would just about do i think. The price, as we are mere people who dont earn £300 a hour has to be within budgets - so lets say £25-30 a month...
You can see from this its a chicken and egg thing, NTL/BT/Whoever wont go rushing out and laying Fibre to ever home "just in case" they sign up for Boradband, they dont have the money to chuck around "in case" it works.
Lastly then, here is a couple of examples of where it has worked...
1. I speak to Telewest for a FAST internet line for the Library, as the main office is a mere spit throw away, they can happliy supply a 45mbit line for a VERY cheap cost (a cost most home users would pay easy). but of course not everybody is down the road from the main Office.
2. NTl did a trial, some lucky so and so (london) gets a 155mbit line for what, £20 a month (including TV + Phone). This never lasted (as a trial) but they did trial it for some reason...