The MetroCast technician came today and checked the box across the street, the box at our house, the output of the modem and the wired output from the router. Got no changes in the download speed. It stayed at about 5.8 mbps per the webmasters speedtest.net. Then he downloaded the test from speedtest.net as follows and got 16.25 mbps. He couldn't explain the difference. He did download Foxfire for me which seems to be a lot faster than Internet Explorer.
http://www.speedtest.net/result/2634712488.png