I look at rankings this way. There are two issues, (1) are they accurate, and if so, (2) accurate about what? First of all, they are a little old, based entirely on a 2008 survey of "reputation." In other words, they are not based on data about resources of the school, the success of their grads, or anything like that. They are based on reputation opinions. Okay, so let's say they are reasonably accurate rankings of the reputation of a school. The question would then be, how valuable is this to a graduate? I would say that it could be fairly important in getting a teaching job (after all, to respond to one post, you don't have a shot if you don't get an interview), and maybe gallery owners would give you a harder look. Not sure the consuming public cares too much though. The art and entertainment bizz's aren't so "linear."
Put a different way, there is (1) credential value, and (2) educational experience value. The problem is, it is fairly easy to measure the status of an institution as an applicant, but it is fairly hard to REALLY know what your educational experience is going to be like, apart from a vibe you get during a campus visit, or an assessment of the resources available to you. That said, the big question is how important IS the credential value. I'd say it is very high for the top 10 schools or so, but the returns diminish after that. But again, how do we really know what the educational experience is going to be like?