Like its cable compatriot Time Warner, Comcast isn’t just latching onto the established managed Wi-Fi networks in coffee shops, restaurants and shops. It’s building an extensive outdoor hot zone network as well, exposing its access points to the elements to capture high-traffic pedestrian zones and public gathering spots.

Until now Comcast has been mainly concentrating on the eastern seaboard where it has built extensive networks using Ericsson BelAir Networks equipment in and around Boston; Philadelphia, Baltimore, Washington, D.C., and Richmond, Va. But now it has cast its eye on the left coast. Comcast has also struck up roaming pacts with Time Warner and Cablevision that will eventually allow them to create a unified national hotspot network, though so far its only been implemented in New York City.

Comcast’s California rollout doesn’t appear to be quite as dense as its mid-Atlantic deployment, but it covers a lot of markets. A complete list of cities and towns is at the end of this post, but you can also see detailed coverage maps at the Xfinity website.

Comcast’s Wi-Fi hotspots are detailed in red

As with its east coast network, Comcast is offering Wi-Fi access to its residential broadband customers for free. For non-Comcast subscribers, the cable operator is selling access by the hour, day and week. The SSID for the network “XfinityWiFi” and can be accessed from any laptop, tablet or smartphone.

Apart from the Bay Area the new Comcast network is in the following markets: Aptos, Atwater, Buellton, Cameron Park, Carmel, Chico, Chowchilla, Colusa, Corcoran, Davis, Diamond Springs, Dinuba, El Dorado Hills, ElkGrove, Fairfield, Folsom, Fresno, Galt, Grass Valley, Hanford, Kerman, Lathrop, Lemoore, Lodi,Lompoc, Los Banos, Madera, Manteca, Marysville, Mendota, Merced, Modesto, Monterey, Murphys, Nevada City, Newman, Oakdale, Oroville, Parlier, Patterson, Placerville, Rancho Cordova, Reedley, Roseville, Sacramento, Salinas, San Andreas, Sanger, Santa Maria, Selma, Solvang, Sonora, Soquel, Stockton, Tracy, Tulare, Twain Harte, Vacaville, Vallejo, Visalia, Willows and Yuba City.

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Most of the new roaming functionality will be in New York City and the surrounding Tri-State area, Los Angeles, Tampa, Orlando, and Philadelphia as those areas have overlapping cable and Wi-Fi coverage. The group will be adding more cities and coverage areas, however. Signing in to a Wi-Fi network out of your home coverage area should be seamless: You’ll simply use the same credentials as you would on your own cable operator’s network.

As I’ve mentioned in the past, not only will consumers be happy with this broader Wi-Fi coverage, but so too will the mobile broadband network providers: Free Wi-Fi — even from someone else’s hotspot network — helps to offload data from 3G and 4G networks. Single sign-on while roaming on different networks makes this an easy win for consumers while cable providers can use the expanded coverage as a marketing perk to attract new consumers.

Sounds like a win all around to me and to my colleague Stacey, who said this two years ago after speaking to the folks at BelAir Networks, maker of wireless solutions, and now owned by Ericsson:

“So will ISPs take the consumer love of ubiquitous broadband and carriers’ need for offload to the next level and create the equivalent of roaming agreements for Wi-Fi? Greg Williams, the new SVP of corporate development at Bel Air Networks, thinks they might. …He wonders if carriers will negotiate with each other and fixed-line ISPs to get access for their wireless subscribers, especially in congested cities such as New York or San Francisco.”

Two years later, and it looks like the Wi-Fi roaming revolution is well underway. Be sure to bring your smartphone or tablet with you to get on board!

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Introducing Comcast’s AnyPlay: a set-top box that sits next to your Wi-Fi router and ensures the linear streams being sent over the network are secure. Live streams are then delivered over the home Wi-Fi network to compatible devices. Right now, that means the iPad, through Comcast’s Xfinity TV app. But the cable operator is promising it will add support for the Motorola Xoom tablets.

Like other offerings from cable providers like Cablevision and Time Warner Cable, the live streams are only available in the home, when a user is connected to his own Wi-Fi network. That will limit subscribers’ ability to stream to the mobile device anywhere — but for families with kids who want to watch programming other than what’s on the living room TV, it could be a potential value-add.

Now here’s the real bummer for most Comcast customers: While the AnyPlay device is free, it’s only being rolled out to a limited number of users in certain select markets. The device will be made available just to Xfinity HD Triple Play customers in Denver and Nashville at launch, with plans to expand in the coming months.

Still, adding live TV to tablets is a big step forward for Comcast, and builds on its TV Everywhere initiative, which gives subscribers access to more than 8,000 hours of on-demand movies and TV shows from supporting networks on its XfinityTV.com website and on the Xfinity TV app.

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