JetBlue's 'All You Can Jet' pass sells out

— -- JetBlue suspended sales of its unlimited-flight pass Wednesday, saying it had to do so because of strong demand.

JetBlue debuted its $599 "All You Can Jet"promotion Aug. 12, a deal that garnered nationwide attention for offering customers all the flights they could take between the airline's 56 cities starting Sept. 8 and ending Oct. 8.

"Sales of the pass have really exceeded all our expectations," JetBlue spokesman Sebastian White says.

When it announced the deal, JetBlue said customers would be able to purchase the passes through Friday night or "while supplies last." The supply ran out before the deadline.

"We want to make sure that we don't sell so many (passes) that it becomes a challenge for people to find seats," White says, explaining why JetBlue drew the sale to a close earlier than expected.

As noteworthy as the deal was the publicity it stirred for the New York-based carrier. The promotion was still grabbing headlines this week, seven days after it was unveiled. Local TV stations, newspapers, travel websites and blogs were still running with a story that got play from NBC's Today Show to celebrity blogger Perez Hilton.

Some industry observers say they were caught off guard by how much publicity JetBlue got.

"I'm totally surprised by the amount of attention the promotion has earned," says Henry Harteveldt, airline analyst at Forrester Research. "It's an extremely creative promotion, though, and creativity is something sadly absent from airline marketing and promotions. It's the kind of offer that makes you sharply inhale when you see it — it's so good that you almost can't believe it."

Fare sales have been common this year, as airlines grapple with falling demand amid the recession.

But none captured the same media gusto that JetBlue's did, and — unlike previous, more traditional sales — no major carriers tried to match JetBlue's pass.

The more complex operations at the nation's biggest airlines — so-called "legacy carriers" such as Delta and American — likely played a role in preventing those companies from rushing to match the offer.