The best sports in town...

There are 21 metro areas in the USA that have 3 or more major league sports teams. 
Anaheim-LA, the NYC area, the "Bay Area", and the DC-Baltimore area.
Also, Atlanta, Boston, Chicago, Cleveland, Dallas
Denver, Detroit, Houston, Kansas City, Miami, Minneapolis
Philadelphia, Phoenix, Pittsburgh, Seattle, St. Louis, Tampa.

So, for each city in this list
    for each sports club in the metro area
        for each of the last five metro seasons
            award points based on finish
            10 for a league title
            6 for runner up
            3 for making conference finals
            1 for making final 8.
Then, for each city, find out which club has the highest score, and declare them "King of the City."

The clubs that can say that they're the kings:

NFL: Arizona Cardinals, Atlanta Falcons, Baltimore Ravens*, Minnesota Vikings, Pittsburgh Steelers*. MLB:  New York Yankees*, Philadelphia Phillies*, SF Giants**, St. Louis Cardinals*, Tampa Bay Rays, Texas Rangers. NBA: Miami Heat**, Lebron James in Cleveland. NHL: Boston Bruins*, Chicago Blackhawks**, Detroit Red Wings. MLS: Colorado Rapids*, Houston Dynamo, LA Galaxy**, Seattle Sounders, Sporting KC. * marks number of titles in the last five years.  (The Cavaliers only saw playoff appearances with Lebron, and with his departure, the Cavaliers fell back to standard Cleveland heart-breaker levels)