I must say that strangely enough, I would agree with some parts of this statement, although I would phrase it differently, and it would (hopefully) be a more accurate representation of the truth. First, I was here last year, and got into a good school. I am revisiting to see if I could help. I go to an ivy league school, and I would agree that the faculty and the department takes immense pains to ensure that their students get placed into tenure track jobs in good schools. To rephrase StrangeLight's statement more precisely (and with less prejudice, I think), more faculty in Ivy League schools are more likely to watch out for their students than at other schools. HOWEVER - they also *have* to do that to keep their reputation up, and not solely out of the goodness of their hearts. Further, this does not mean that other faculty elsewhere would not do that. Baseline: make sure that your you *really* get along with your adviser. Not just in terms of fields etc - but as a personal connection. I am friends with my adviser. well, almost.
The second "truth" about a good school (not only Ivy L ones) is a good library. Most university libraries are good for some things, and not so good for most others. Please factor in library resources (specific to your field) in your decision - it would be VERY annoying to get most of your books via inter-library loans.
Third, I would like to point out that most students, esp. in History programs, change their minds about their specific projects after they get to school. In part due to evolution of projects, but sometimes because you meet a new (and different) faculty who changes the way you think, and suddenly you realize that you didn't want to be say an early moderninst anymore, but actually say a East Asianist. This may sound absurd, but I have met people who have made similar radical changes. Most good departments would be able to handle such a change. Your funding would continue, and the department would be as *strong* in that field as well. Please factor that in your decision as well!
Best of Luck!