Earthlink has been signing up a stream of cities in its plans to build and sell metro-sized WiFi networks — Philadelphia, New Orleans, San Francisco, Anaheim. But not all cities are proving easy markets to crack. That’s partly why Earthlink has been talking to the owners of major sports stadiums in various markets, looking to unwire the arenas as sort of a proof of concept to show to cities: ie. Look Mayor, I unwired your baseball stadium, so why don’t you just give me the city contract?

Earthlink’s VP of Product Strategy & Marketing for Municipal Networks, Cole Reinwand, says Earthlink is talking to the owners of the Oakland Coliseum, where the A’s and the Raiders play, to unwire that stadium. Reinwand says WiFi in sports arenas can offer real time stat-tracking, or say, streaming video to premium seats. A stadium WiFi deal would be a good thing to show to the city decision makers, he says, particularly while Oakland is in the process of studying its options for a city-wide WiFi network.

Earthlink is also talking to other stadium-owners in major cities like Cincinatti. We’re not sure how popular WiFi in stadiums will be — do Athletics fans like to focus on their laptops when they can see The Big Hurt hit one out of the park? The San Francisco Giants stadium has had wireless network for a while, but we’re not sure how many people actually use it. Sure GigaOm readers are used to baseball metaphors by now, but hey this is actually broadband via baseball.

Photo by Niall Kennedy via Flickr