Schools like Harvard and Princeton, do they even accept applications from students who take a gap year or have done a PG year?
Do they view that as positive or negative if the students have made meaningful use of their time? How would the acceptance rate differ from a student who applies to colleges in grade 12?
When I was looking through the site there is an old thread on this. It was a group of people who communicated with each other during their Gap year and where they got in at the end. These are people who are college freshman now. They took one either because they did not like their acceptances or because they wanted the time. They were applying during their Gap year and seemed to get into better colleges. One thing, the general rule is if a college did not take you as a senior they are probably not going to take you after a Gap year unless you cure the common cold during that time. However, similar schools that you did not apply to, are more likely to if you did something worthwhile that as the above poster said, set you apart.