To add another data point, Albuquerque (ABQ) has a free hotspot in the public lounge above the food court for Concourses A & B. It's a very pleasant place to sit (big comfy leather couches looking out over the airfield, quiet, isolated -- I liked it better than most of the Red Carpet Clubs and USAir Clubs I've been in ^ )

SSID = sunspot if I recall correctly (I've already cleared it from my list, as I won't be flying through ABQ again in the foreseeable future). It's a Cisco wireless AP, plainly visible (go up the elevator, then look up and to your left as you get off).