Wingnut -
The Port Authority which runs the NY airports is either in the dark ages about this (from what I've heard, stating that there cannot be multiple wifi networks at the airports in the interest of safety and other logistical requirements) or in the process of setting up their network in order to financially capitalize on the service. Right now, according to the DL Crown Room agents, T-Mobile has tried to set up in their facility but has not been allowed in.