-I really think "top 10" doesn't tell the whole story. The JH and Harvard match lists year in and year out are just incredible. These students not only match in whatever fields they want, they also match where they want. Many students from other "top 10" schools would just be happy to match ent, uro, opthalmology, ortho, etc at a solid university program. JH and Harvard students match these specialties at top 10 programs. And if they decide to do IM, it's almost always at MGH, Hopkins, UCSF, or maybe stanford. The notion of top 10, top 20, top 5, etc is probably talked about too much, but there is a clear difference between the match list of Hopkins and Harvard versus other schools ranked #3-10. Schools like Umich and Columbia have great match lists, but they aren't on par with JH.
-In my opinion, the big thing with schools like Emory, Northwestern, Chicago, Pittsburgh isn't so much the overall match list, but the preferance given to their own students. Emory had over 40% of its class last year match at emory. Many of those matches were rads, urology, derm, opthalmology, etc. If you wanted to do your residency at Emory(and especially if you wanted IM), you'd have a really great shot to get it from emory school of medicine. I'm not saying you can't do a residency at Grady having gone to a state school, but I think it would be a safer bet coming from emory. I can't speak for other schools ranked #10-25, but Emory didn't have that many "oh my god" matches. Out of 105 or so matches, I counted 26 that were really really special(~25%). At JH and Harvard the numbers are closer to 90%. I'm not sure what the numbers at schools like Duke and Penn are(55-60%?)
IMO(as far as matching goes),
JH/Harvard >>>>> schools #3-11 >>> schools #12-25 > state schools and mid/lower tier privates
Once you get past #25 or so, I don't think there is any advantage. Assuming equal credentials, I don't think a student matching from GW would be in a better position that a student matching from Texas Tech....unless of course it was either the GW or TT programs the applicants were shooting for.