local is not social
dont be confuse about two different concept
local media = near you
social media = similar to you
differences ?
local means not far, you can localize on mobile near to you and the interest is time based. at a T time your are at a L location
social means used like you, of course you can use mobile to localize but the interest is product centric. in a perfect world the time is not important on the social concept.
=> facebook is social, foursquare is local.