And just to provide a little balance for the glowing review by jtsscoop....
DD was recruited for the IB program in high school. We attended informational meetings, talked to IB parents and students, and did a fair amount of research on the program.
Disclaimer: the info below will be infused with my personal opinions, so take it for what it's worth.
I think whether the IB program makes sense for you/your student depends on what you/they are looking for from the program.
Quality education and general college prep = I think it's great.
A specific edge in the college admission and/or scholarship process = may not be so great.
(although as per the post above, it may work out that way for some folks)
I have no doubt that the IB program provides a rigorous, integrated education that helps prepare students for college; no matter where they choose to attend. The "extended essay" requirements are probably more intense than anything I faced the first few years of my college coursework. It wasn't until I hit some of the toughest upper division courses in my major that I had to do that caliber work. I also think the community service requirements are admirable.
If my child were planning on applying to any universities abroad, I would definitely encourage them to consider the IB program. However, while I think more US universities are beginning to recognize the IB program; many (if not most) still do not give any additional weight to IB coursework, nor do they necessarily recognize an IB degree when making admission/scholarship decisions.
DD wanted to attend a university that requires a very competitive high school GPA, and gives no additional weight or college credit for IB courses, but does for AP courses. It made sense for DD to go the AP route instead of the IB route.