As BT own what is known as the backbone and everything apart from cable goes through that, you have to either buy your internet access from a cable company, or a company that pays BT for the use of their infrastructure.
BT has always been the real problem in this country. Because they are known as a blue chip company as far as the stock market is concerned, they've been afraid to invest in improved infrastructure and because of their monopoly they have held up progress with regard to communications systems in general. If a company like virgin says they are going to invest millions on their systems, their share price goes up, but if BT says the same thing, their share price goes down.
Because they are blue chip (a bankers share) the majority of their shares are held by pension funds and institutions ect and that is because they are regarded as a safe bet, not too exciting, but pretty safe as far as the share price is concerned and always likely to pay a reasonable dividend. Unfortunately this has led to them just sitting on their hands and trying to maximise the income stream from what they already have a monopoly on, the infrastructure.
Iain.