The reality is: It can't help you get into the academy. Matter of numbers. There's approximately 10,000 applicants to the academy per year. However, summer seminar can only take a small fraction of interested parties. Use to be only 2 sessions with 350 applicants each. Now there's 3 sessions. Even if it's still 350 applicants each, that's just over 1000 who can attend summer seminar.
Now, for the unofficial thoughts. The academy, as well as you ALO and congressman who will be interviewing you, want to see that you have challenged yourself. They want to see that you've taken the most difficult classes in school and are involved in many extra curricular activities. So, applying for summer seminar looks good with these people. Even if you don't get accepted, it looks good that you applied. Also, remember that when they are choosing candidates for summer seminar, most times they don't have any SAT/ACT scores, or even your junior year grades. So there's not a lot to compare you with someone applying to the academy who hasn't applied for summer seminar.
Summer seminar is mainly a way to get those interested in the academy, a chance to get a taste of it and decide if they really want to continue with this journey. I know first hand, many who went to summer seminar and decided that the academy wasn't for them.
So there you go. No, it doesn't officially count. It can't. It would be unfair to the 90%+ who WANTED to go to summer seminar, but there just isn't enough slots. However, for those who interview you, it's another extra curricular that you participated in, and it shows your interests are sincere. So in that respect, for the impression you make on your ALO and congressman, it sort of can have a small impact. Hope this helps. Mike.....\
P.S. Yes, they will do the CFA during summer seminar. But for "Air Force" it doesn't count as the official CFA test. They have to take that back home. Now, if interested in the army or navy, they do allow the summer seminar test to count. Army I'm almost positive, navy, I think they do. mike...