That's interesting...and good to know. I was mistaken--the press release actually says Song's 33" is "as much as" (not "more than") any other low-cost airline. My apologies to Southwest.
Still, it seems like 32" is as much as one can hope for on most airlines--even on long international flights--and I've recently had the misfortune of experiencing Continental's 31" pitch on their 737-800 transcons out of EWR. Once Song starts flying coast-to-coast, with IFE, more room, and good food (albeit for a small fee), it's not JetBlue I'm worried about--it's the major airlines!
Which raises the question of how much Delta is willing to cannibalize itself. I don't think the folks in Atlanta are stupid--they know what's bound to happen if the LCC product surpasses mainline. This is why I believe that Song is actually a way of testing out ideas that might ultimately appear throughout the Delta network, in some form or another. Will DL be the first major to do away with first class on domestic flights, in favor of a "premium" low-cost economy product? It won't happen overnight, but I won't be surprised if it does eventually...it might be their best hope for long-term survival.