If you look at the two pictures here, you will clearly see that the websites are not from cox.com and that the messages seem to be injected into the bottom right of the screen, even taking away screen real-estate from other ads and content. Many would say that this is very intrusive. Much more intrusive than actually being helpful to the users.
I have yet to see the code, but if I were to gander, it may look a little something like this:
$("body").append($("<div style=’background-color: white; border: 1px solid gray; padding: 5px; position: absolute; position: absolute; top: 0px; left: 0px;’><div style=’font-weight: bold;’>Cox Message:</div><div>This is a warning Message.</div></div>"));
Granted that this example that I whipped up in just a couple of seconds isn’t as “feature-rich” as the Cox message, but give it just a little bit more work and you can put just about anything, anywhere on a page if you have access to the packages that are being sent back and forth. All of these ISP’s have ways to read your information, scan, and send to you… this just puts it right in your face.