...One problem with using this language to describe medical schools is that there are really no "low tier" med schools in the US. Just check match lists, and you can see that while the top schools may have more prestigious lists, even the schools considered lower match plenty of people into good programs. There is not nearly as great a range in med school quality as there is in college quality.
That said, there certainly is a hierarchy of reputation, and when applying to a residency your med school is a factor. The general rankings people assigned to your list of schools seems accurate to me, too. In some ways, though, I think it may be more appropriate to split med schools into two groups, the more prestigious and less prestigious, rather than three. I suppose if I were to do that I'd put about 50 or so schools in the more prestigious category and the rest in the less prestigious. And within those groups there will still be more and less prestigious schools, but much of that is influenced by regional factors or perhaps even speciality reputation (which is usually based on residency programs but may filter down to influence the school itself).
Just my thoughts.
edit: It's possible that there are 5 to 10 schools at the top which have a much higher reputation than all the rest. Schools like HMS, JHU, Yale, maybe Wash. U...I'm not sure on the exact schools (I personally haven't found it necessary to pay much attention to them for my own application ). Aside from those schools, the 2-part ranking system still seems to me to be appropriate..
