I brought home a Motorola DOCSIS 3.0 cable modem today so that I could upgrade my Internet speed to the maximum available in my area. I plugged it in, went into the modem's menus at 192.168.100.1, and watched the status until it had established carrier and received the carrier update from Comcast and rebooted and went online. Then I plugged www.google.com into my browser window and it put me into the Comcast provisioning GUI. I selected that I was a "technician" (since the "customer" option requires Windows and I of course am on a Mac), put in my account number, and it pretty much did everything automatically from there to link my new modem with my account and provision it for use on the network, just requiring me to hit a "Next" button from time to time between steps. At the end of the process it then put me on the Internet, and here I am.
This is a serious improvement over what the user experience used to be like when you upgraded your cable modem, when you had to call Comcast's service center and have them provision the modem and it could take hours sometimes to accomplish it. So as much as I like to dump on them as "Compost" and "Comcraptastic", this is at least one thing where they've gotten their shit together quite well, thank you very much.
-- Badtux the Geeky Penguin