As a followup, the following was on Brancatelli's website the other day:

"Southwest Airlines today announced its first cities from Philadelphia and that means fare relief in six markets when the low-fare giant begins flying on May 9. Southwest says it will launch its Philadelphia incursion with daily nonstops to Chicago/Midway; Las Vegas; Orlando; Phoenix; Providence, Rhode Island; and Tampa. And since Southwest caps its walk-up nonstop fares at $299 each way, that means substantial savings in all six markets. US Airways, the Philadelphia incumbent, now charges walk-up fares of $374 to Las Vegas and between $428 (Phoenix) and $477 (Chicago/O'Hare) one-way on the other five routes. And don't forget that another high-fare market, Boston/Logan, gets relief beginning January 16. That's when JetBlue Airways launches nonstops to Florida (Orlando, Tampa and Fort Lauderdale), Denver and its Southern California hub at Long Beach. Like Southwest, JetBlue walk-up fares top out at $299 one-way. United currently charges $676 one-way to fly the Boston-Denver route."