We got our tix yesterday afternoon, just as they were releasing them. We mananged to get Frequent Flyer tix for all 4 of us on the way down, and two of us on the return, so just two one-ways to purchase. That was a good thing too, bcs the one-ways ran us $307.80 apiece. Still, we are thrilled that we got seats on our favorite airline for perfect travel times for our February trip at a price we were OK with.
As I was booking the frequent flyer tix with the JetBlue rep, i asked why the fares might show up on Kayak and Sidestep before they do on the JetBlue site. The JetBlue rep theorized that when JetBlue is loading the fares onto the website, that they are available to the search engines (Kayak and Sidestep), but not yet to the general public on their website. It's a theory.
I any case, I was able to get my airfares again, searching on Kayak and buying from JetBlue. It's too bad they aren't inexpensive for the times we want, but not unexpected. They are going to sell out all of those flights going from cold places that have February vacation down to sunny Florida, so they're going to do it for good money if they want to stay in business.
And remember, JetBlue is a low cost airline; that means that their operating costs are low, and not necessarily that their fares are low.
Good luck everyone!