The M7 is real...they have come out and said they meet to discuss the state of B-schools. They definitely all are working together somewhat to strengthen their standings.
One way to judge schools is to look at the highly sought after post grad jobs. How many hires do they get from the sought after companies like McKinsey, BCG, Bain, GS, Morgan Stanley, L. bros, M Lynch...etc. If a great proportion of the folks heading into consulting go to the Big 3 then obviously its a very highly regarded school.
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Kellogg Class of 2010...still active and willing to help. However, I do not do profile reviews, don't offer predictions on chances and am far to busy to review essays, so save the energy of writing me a PM seeking help for these. If I don't respond to a PM that is not one of the previously mentioned trash can destined messages, please don't take it personally I get so many messages I have a hard to responding to most. The more interesting, compelling, or humorous you message the more likely I am to respond.