Grad School Rankings

How much do they matter? Who ranks schools reliably? What are typical criteria used to compare programs?

I have the APA publication Graduate Study in Psychology, but even with that it's hard to know where to apply. The schools I'm looking at (for a Social Psychology Ph.D. program) are Stanford, UC Berkeley, UCLA, University of Michigan, Ann Arbor, University of Connecticut, and Claremont Graduate University. Stanford is probably just wishful thinking. I'm thinking that I need to select a couple more (non so highly ranked) programs to apply to to maximize my chances of getting in somewhere.

For those of you already in grad school, do you have any advice to offer? Should I look at programs strictly based on the research interests of their faculty, or should I take the prestige of the university into account? I'm looking for a career in applied social psychology, not a professorship, but still. How much does rank matter?