Again I disagree, inenvitably it was Virgin that brought on the problem by advertising as 'unlimited' 20Mb/50Mb connections, thus attracting all the bandwidth hogs who need there linux iso's faster.
Fair enough there are issues of oversubscription in some areas, I know of this first hand - however its unproven but I reckon with Iplayer, multiple PC usage etc the average household would use 15-20GB per month.
However the oversubscription would be eased somewhat by less bandwidth hogs, Virgin dont have the cash to upgrade there infrastructure as needed so resort to STM. They advertise as the fastest unlimited connections then create their own problems when people want to use their connections as they please hence STM. Its a vicious circle, it really is but 300GB+ a month bandwidth usage really makes me sick - abuse of a shared resource etc.
Look at BE/O2, they make it a point that they dont throttle/cap and they are a huge company making massive profits (imo). However I reckon some form of traffic management will come in time... Look at Sky they removed the FUP and now advertise as unlimited, traffic management? you betcha - but as long as the userbase gets nice speeds without any hassle I bet 98% of the userbase is happy and dont even notice - Virgin could learn a lot of lessons. No STM needed as such.