On Your Six and G4G5 are right on the money. I had the opportunity to go to NJA when I came on with Pinnacle, and boy do I wish I had taken the NJA route. If I was where you were, there's no way you could pry me out of that seat unless FedEx called and even then it'd be a tough choice.
jetBlue is a great company with great people, but their growth IS a little scary although I'm not worried about a dual fleet - AirTran seems to be having no problems integrating a B717 and B737 fleet into their daily operations, I see no reason why Blue couldn't do the same thing.
Don't listen to Longhorn, he's drinking the kool aid. (Couldn't resist buddy, excuse me, Mr. 969 seniority number.

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It may be about the schedule. 7/7 isn't for everyone, and 12 days off on the reserve schedule doesn't sound all that fun either. I like doing a 4 day trip, being off 3 or 4 days, then going back at it again and I commute; I have kids, I don't like being gone more than 3 or 4 days off in a row.
It may be about the pay. NJA tops out MUCH higher than jetBlue ($167k DA2000EX versus $137k jetBlue top CA) and I can't imagine that changing drastically without a union in place at jetBlue which I don't think is going to happen for a LONG time, if ever.
It may be about the flight attendants, or guaranteed schedule or any other number of things, the best thing you can do is post a list about what you like about both lifestyles, then see what jumps out at you.
Now that I'd have to move, NJA is no longer on my radar screen, I'm just not able to do that with family concerns, so I'd have to be able to commute. Everyone has different issues important to them, but if I was in your boat (pre T.A. language on domiciles), I wouldn't move.
What's important to you? What's your driving issue to leave Netjets for? Those are what we'd have to know in order to help you make a decision and since those are pretty private things many times, you're probably on your own.
p.s. What G4G5 said about type ratings and job stability and future job security bears re-reading, I can't stress that enough if you're going to stay on the corporate side of the world. Good luck!