Last week, I reported on JetBlue's innovative All-You-Can-Jet program, allowing participants to pay $599 and fly as much as they want from September 8th through October 8th. If you were interested in the program, I hope you got your pass already, because it's sold out.

I spoke to a JetBlue spokesperson about the program this morning. He told me that the company was not releasing the figures for how many people were enrolled. He said that demand for the passes, however, was quite strong. So strong that the airline decided to close the program a few days earlier than planned to insure that those who purchased the passes had ample flight availability to make full use of the program. Too many participants could have caused the flights to be too full, hampering pass-holders' travel plans.

If you missed your chance to get the passes, stay tuned. Although JetBlue has a wait-and-see attitude about whether it will bring back the program in future months, the company was very happy with the response and buzz it created. I would imagine that if the program turns out to be profitable -- meaning all-you-can-jetters don't fly more than JetBlue anticipated -- then it will offer the opportunity again.

I asked if JetBlue would disclose any data about what types of travelers were finding the passes most attractive, but it has no such plans. So we'll have to keep guessing the breakdown between business travelers, unemployed Americans, the retired and recent college graduates. Participants have begun booking trips, but no dominant trend for destinations has formed, as booking seems to be well spread out at this time, according to the spokesperson. I hope the airline ultimately releases some data about the travel patterns of these pass-holders -- it would be really interesting to see what destinations are most sought after by travelers with unlimited travel access.

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