If the JetBlue pilots feel they need a union, they should organize.
As a 25 year ALPA member, I caution them STRONGLY against certifying ALPA as their collective bargaining agent. ALPA is a toothless dinosaur. Functionally, it's pretty much dead, but the momentum of its bloated mass seems to keep it moving along.
Form your own in-house union. Maybe modelling it on the successfull SWA pilots union would work for you, or maybe something high tech as the failed attempt years back by USAir pilots to extract themselves from ALPA. Just don't flush your dues money down the ALPA toilet. ALPA is mostly concerned with ALPA, not your individual airline. The ALPA "expertise" which you would get to tap is "expert" in furthering ALPA's agenda. That agenda can very well be 180 degrees away from what is best for JetBlue pilots, but the ALPA "experts" will tell you differently.
The JetBlue pilots who have been ALPA members in the past can tell you that the purported unity of all airline pilots under one ALPA organization is a sham. ALPA is merely an association of individual airline bargaining units (Master Executive Councils, or MEC's) who bargain with their carrier independently and are subject to being whipsawed by the industry. A unified ALPA could prevent this, but the real ALPA is helpless.
Good luck with your careers, and with unionization if you decide you need it. Just don't waste your hard-earned dollars on ALPA dues.