Your Comcast Xfinity router may now be a WiFi hotspot

Comcast has just transformed part of Houston into a WiFi commune by activating 50,000 residential Xfinity routers, according to the Houston Chronicle. The new service will give any Comcast client free WiFi access via those "xfinitywifi" hotspots, and is just the beginning of a larger rollout. ... A lot of customers now broadcasting WiFi may not actually know they're doing so, however, since Comcast opted them in by default -- though it did warn users by mail.

Well, that's one way to do it... secretly get a lot of your customers to place your broadcasting equipment in their own homes, then one day just flip the master switch.  Ingenious and creepy as the same time.  I can see why people want to opt-out.