In June of last year Comcast announced
that the company was launching a new, Fon-like effort that involved new router firmware that turns your gateway into a publicly-accessible hotspot. More specifically, update routers would now offer two signals: one being yours, and the other being a "xfinitywifi" SSID signal providing free Wi-Fi to other Comcast users in your general area.
Fortunately, users can disable this functionality if they don't want to share their bandwidth with strangers, but Comcast says this functionality is enabled by default.
The public usage also thankfully doesn't count against your Comcast usage cap (if you have one in your market), but it will obviously consume some of your bandwidth (though Comcast claims they push a little extra bandwidth when the feature is active so it all balances out).
The effort has been seeing scattered deployment on a market-by-market basis, and in a few instances the new functionality has confused the hell out of some Comcast users
, who didn't know they'd suddenly be offering free Wi-Fi to others.
This week the functionality appears to be getting turned on for Houston customers
. Much like the national deployment Houston's launch appears staggered, with Comcast enabling the functionality 50,000 Houston users at a time through the rest of the month. Other Comcast markets will see the update as the year rolls on.