That's about our SXM vacation time as well, and we usually book in October. We were watching flights and delayed booking in Oct. this year but just pulled the trigger and booked two nights ago. Two people, each with a bag, no other frills, on JetBlue - PWM (Portland, ME) to SXM - $1,101.02 was the total bill.

In the past 8 years we've kept Air to around $1K or less, and when we've booked it, we've never seen it go down appreciably in the ensuing months leading up to our trip.

This time Airfare has been around this $1.1K price all during Oct. We were getting the feeling that it isn't going to get much cheaper, and since everything has to go up sometime we stopped the waiting and resigned ourselves to the fact that we'd be paying the extra $100 or so.

Ultimately our delaying did cost us even a little more. While we were waiting to choose and lock in airfare, our destination, Club Orient, was apparently filling up for early June, so much so that they had already kicked in their new flex pricing, and on four of our 11 nights the Minisuite prices rose 5% (about 30 Euro total)