Enh. If all your friends were good enough to get into MIT/CMU/Stanford in the first place they're more likely to be employed or well placed in business. If it's worth the added headache/tuition is debatable, but certainly you have far better networking opportunities as the 50th percentile at an exceptional school than being the shining star of ITT.
No doubt; I guess what I'm getting at is that the onus is still on the individual students to be good at what they do. Yes, you're more likely to find good people at good schools, and there is value in that networking. But just having access to those contacts is not going to mysteriously boost your odds of landing a job. You still have to leverage them - and your own skill set, more importantly - to get in. And it's not like you can't develop contacts with people who went to other schools; you get a small leg up by seeding your social network with some of those people, but in the grand scope of things, I'd rather know people from 20 different schools than 20 people from MIT.