As others have said, the IB program is definitely beneficial towards applying to the academies. Academically; it is usually the most challenging classes. Nothing against AP classes; they too can be very challenging; but the IB program is a program. In other words, ALL classes on your schedule are at the highest difficulty instead of just a couple. Now some people take ALL AP classes. That would be equally as challenging.
Another thing about the IB program, is that it's international and standardized. The class that a 17 year old in Colorado is taking, is the same class a kid in Wyoming, Florida. Paris, Tokyo, or London is taking. Also; the IB program isn't just about the academic classes. It also revolves around volunteer time, community service, and improving yourself as a complete individual. Basically all of the things the academies are looking for.
So by all means, if you have the opportunity to enroll in the IB program, definitely go for it. Granted, there are only about 1000-1200 degree IB programs in the United States, but if your school has it, and you have the capabilities, then definitely go for it. Warning, it is very challenging. Not only academically, but the 200+ hours of volunteer/community service. Plus, it's very time consuming.
There are some that can do the IB diploma program and still do varsity sports, member of clubs, class officer, boy's state, etc... These are the individuals that the academies definitely notice. If you can do the IB program with it's academics and community service; and still find time for sports and leadership, you definitely have a great chance of getting an appointment. Remember; the academies and most high end universities want the complete person. Not just the academic star. So being in the IB degree program, even with the community service, but not doing sports and leadership isn't going to help you. But if you can do the IB degree program; Community service; extra curricular; sports; and leadership..... Then the academies and most people realize that there is literally nothing more you could have done. Best of luck to you. Mike....