I feel (meaning I have something to say but no facts to back it up) that rankings can give you some idea of how schools compare. They do not help in the least to tell you if you'll do well or even like certain schools.
I use the rankings simply as a relative measure after reviewing the criteria used to rank the schools.
My years (oh, so many) have taught me that it's not so much the school as it is the person going to the school.
And that is the sum of my wisdom on the subject. I think I'll go lay down for a nap.