Since I live in Houston, I have to tell you that we have three airports with commercial service within Houston City Limits: IAH, HOU and EFD [Even though IAH is in a disjointed part of the city, it is on City of Houston land.]
Plus, we actually have scheduled air service on Continental Express between EFD and IAH.
Most of the above U.S. examples don't have two airports in the same CITY, with the exception of JFK/LGA & ORD/MDW.
[This message has been edited by rkkwan (edited Jan 06, 2004).]