From what I know and have learned from a partner from a big law firm, if you are in the top 10% then you will be looked at by a big law firm. I've been confused about the economy and feel sorry for top grads at schools like Columbia that don't get a position at a big law firm. This confusion has lead me believe the advice of the partner and draw the conclusion that with doing your best and being great at what you do ensures that you can achieve your dreams from any school if you play your cards right.
See my post earlier in this thread: viewtopic.php?f=2&t=137613&p=3618869&hilit=+jobs#p3618869
TL;DR version: out of 4,550 jobs at big law firms last year, the T30 took almost 3,500 of them, the rest of the T1 took another 600, leaving everyone else to fight over about 450. Assuming that nobody at a T3/T4 and nobody outside the top 10% of a T2 gets one of those jobs, that's still only about 450 jobs for the 1,900 people that comprise the top 10% of T2 students.
Top 10% at a T2 will get you looks from NLJ250 firms, no doubt. But look at the statistics this way. Even after you fight your way onto law review at a T2, you still have to beat out 3/4 of the other LR kids to get a job at a big firm.