Just because they give 3mps down as a peak, doesn't mean anyone will see it on a steady basis.
Who here that has had their service before has actually seen consistent speed out of it? Most cable users I know are very disappointed with their service, and many only get 1/4 of what's advertised on a regular basis. That's why DSL is a nice option, albeit a bit slower (numbers wise) but always constant.
Arden, how is 1.5mps slow anyways? Must be your area or something, but in my area you get 768/384 or 1.5/768 ADSL options. The limits for DSL lines are 8mps up/ 1mps down on ADSL and around 2.3mps both ways on SDSL.
PLC promised to make a difference, but that is most likely dead in the us. You can thank the Amature Radio (aka Hams) for killing any hope of it.