I've just finished my JO tour (check out tomorrow).
e6bflyer, zippy, and Yardstick hit the nail on the head. Here's my 2 cents:
I got married very early on in this tour, and while we don't go out on a boat for 6 months at a time, it can still be very hard on family life. You are gone about half of your tour, and it's hard to plan for anything, especially early on before becoming qualified. For example: on one of my first trips as a new 3P I had just returned home. The phone rang the next day and I was gone again for two more weeks. I'm not complaining, I knew what the job required, but it's hard to explain that to a new spouse who hasn't quite gotten the whole picture yet. The impression I had given my wife before I moved her out here was that I was going to be home something like 2 months and gone one month. That was wrong. It's sea duty (yes, I know it's in Oklahoma) and unfortunately service comes before self and family. e6b's estimate of 150 days gone in a JO sea tour is a very accurate, but like anything YMMV.
I really enjoyed my time here, and flying the aircraft (actually flying, not droning around on autopilot) was very fun and challenging. We do not land on a boat, but the aircraft is flown using cables and pulleys and aerodynamic balance bays. What does that mean? Well, it means that you have to actually stay ahead of the airplane. It's a beast to fly, especially in high crosswind landing situations and while air refueling. It's a helluva good time once you get the hang of it.
The mission is as close to Groundhog Day as it gets, but as an officer you'll be faced with plenty of leadership opportunities on the road leading a crew of 13 highly trained and motivated people. There are very few places that will allow an O-3 to be completely in charge of a $340 million dollar asset and its crew, TACAMO is one of them. We work with the AF a lot, and I still don't think that the AF O-5s and O-6s that we deal with are completely comfortable with that. Pretty funny, really.
Feel free to PM me with any specific questions you may have. I'll have plenty of time on my hands after tomorrow. Good luck!