You rent the opportunity to possibly call yourself board certified for a few years. There may be a few other things ABPath does, but let's face it, that's the one people care about.
Still, I don't know a way to get the information you're asking for, if you pass. If I got it I surely must've stopped reading at PASS. While I agree it could be useful personal information, as soon as that information is made available it can become another factor in perception of you as a pathologist, in the job hunt, and in your future career. There's a percentage of people that would help, but also a percentage that would hurt. We're already a very numbers-centered profession, born from the days of MCATs. Since the boards are pass/fail, I suppose the theory is...you pass, so it's nobody's business. We risk watering down the essence of "board certification" otherwise. You fail, well, you can use all the information you can get to try to pass next time, so they give you the additional info.