AT&T Wireless is offering Wi-Fi in the terminals and concourses at Philadelphia International Airport: The operator is also planning to build a network at Raleigh-Durham International Airport.
Without extensive and open roaming deals these types of deals -- I'm assuming AT&T Wireless is the exclusive operator here as they are in Denver -- aren't going to see huge usage. Sure, some people will pay $10 to use it but an awful lot more would use it if it was part of a monthly plan they already have with another operator. AT&T's Wireless's unlimited monthly plan is a very high $69 per month.