That seems decent to me! We went last July and after sitting around waiting for prices to come down they almost doubled overnight. I couldn't decide which times I wanted or which airport (I priced Boston, Manchester, Worcester , Providence and Hartford daily). I finally went with Providence after completely freaking out when the prices skyrocketed, and it ended up being $380 each roundtrip. Sometimes I still kick myself for waiting (being indecisive).
That seems like a decent price for Jet Blue. I doubt it will go down much from that. If you are comfortable with the price then I would book. I tend to be a nervous nellie, and worry about prices rising. We usually fly SW out or Providence or Manchester for piece of mind. If prices go down, we just rebook. We can always use a credit for a future trip