The thing is, you pay for 1mbps - So they bump people's speed as high as the line can support.
If you paid for 4mbps, then you have a right to expect that, but the service is "Up to 10mbps", so the lowest you will recieve is 1mbps, the highest being 10 - I have no problem knowing that they have no plans to upgrade me to 10mbps, since in all fairness, even a 512k line would be okay for 90% of my internet usage, the 4mbps just gets my tv series to my pc faster

( and on any well priced uncapped package, you will rarely get more than 1mbps anyway.. )