My account advertises 1.5Mb/s. I haven't checked speedtest.com in a while, but just did so now. I am getting very close to that and even more on one test. My historical average tends to be about 1.3Mb/s or so. Upload is usually considerably faster and this time hit 2.5Mb/s for the fastest one. Unlike cable and DSL, wireless commonly is faster on the uplink for some reason.
That said, I'm not sure that particular test has any practical value. For one, I notice they quote my outward facing IP. That is the same one that is used by at least 3 other (larger) towns, so I suspect that the speeds might not be to my computer. In practice I notice that servers tend to be slow to react, so speed is not so much of an issue because there is a wait for each of the components of a web page, which nowadays can be quit a few and from all over the world. I have a feeling that there are buffers in the system, which also would make speed tests irrelevant.
I think it depends on what you a doing. The internet is not a circuit like with a POTS connection and the traffic shaping devices that are installed at many points are both an unknown and highly variable. In fact I wouldn't be surprised if something like speedtest.com was on the whitelist for most traffic shaping appliances.