I think it’s harder to get into selective colleges than it was years ago because the number of colleges and spaces in the freshman classes therein have remained relatively static while the number of high school students and applications have increased. Some of the ridiculous single digit acceptance rates are attributable to numbers of applications: as they increase the acceptance rate goes down, no matter how qualified or unqualified those applicants may be. However, as the population of the US has grown and with the introduction of significantly more international applications as well as the push for more and more diversity in class make up, it is definitely more difficult to gain acceptance to selective colleges.
You might also find this thread interesting.
http://talk.collegeconfidential.com/college-admissions/501950-old-acceptance-rates.html