I am also experiencing the awful speeds. I did notice that my IP wasn't changing with a router restart, when previously it would always change IP - and my IP is in the range mentioned above.
If I have been placed into an 'excessive' users pool, I certainly don't agree with it. I did ask before signing up if they would be fine with me doing 100GB of traffic every month, and they said that was fine - I haven't even come close to that amount until last month when I did go over a little bit (but their usage meter is trying to claim I downloaded 50GB in 3 days which I am sure I did not).
Last night, I was managing to get 6kB/s off a sourceforge mirror - perhaps I should switch over to dialup until this is fixed.