I am a second year graduate student and my advice is this:
Do not completely igore the rankings of certain universities, but pay closer
attention to the faculty at the institution.  If I were you I would be sure
that the subject or field that you would like to study can be accommodated at
the university or college that you decide to attend.  I would also be sure
that the individual with whom you are studying is supportive of you
philosophies, positions, and interests.  Basically, I would suggest that you
make your decision about where to go to graduate school based not only on
reputation, but on personal contact with the person in your area of study
because if you do not agree with their ideas or feel that they will accept
the work that you would like to do without trying to convince you to do work
that only they are interested in, then there is no point in attending that
school.