Y'know, I was very quick to criticize the name "Song" when I first heard about it, but now that I see the whole concept, maybe some marketing folks were doing their homework after all.
Yes, it's an unconventional name, but it's also one that's entirely different from anything else flying out there, and one that is likely to stick in people's heads. The planes may be hideous, but as sfb correctly pointed out, that never stopped Southwest.
More important, it looks like the whole operation has been very carefully thought out--in effect, it's attempting to do everything JetBlue does and, in many cases, one up them. Not only do they have live TV, but they have more bells and whistles--mp3's, and even games that can be played between passengers (don't underestimate this--lots of parents travel to Florida with bored kiddies). There's even a trendy "Survivor" element, with the option to "vote off" unpopular amenities via the website. Throw in legroom to rival MRTC (or close, anyway), and it sounds like a pretty good product to me.
Selling food onboard is another great idea, one that I liked as soon as I heard America West was going to try it. And from what I've heard, it's looking pretty successful (http://www.nytimes.com/2003/01/28/business/28ROAD.html).
Finally, I think the 757 is a great choice of aircraft. Any route within North America will be easily doable, as will leisure routes to the Caribbean and even Hawaii should Delta decide to take that path someday. And if they ever need more capacity, the 757-300 has even lower seat-mile costs.
This one will be interesting to watch. As has been mentioned before, this could have huge long-term potential for Delta. If they can make a profit against JetBlue and AirTran on the east coast, we might see a similar product--maybe with modifications, maybe not--throughout the whole Delta system.
