I don't know much about Pritzker, but here's what I know about Pitt and I'll make "some" comparisons to Pritzker:
-Pitt #12, Pritzker #27 in NIH research money. That's a substantial difference. While the thought that Pritzker feels more academic might be true, there's plenty of research and academics at Pitt. If anything the med school dean at Pitt is all about research (we make fun of him a lot about that in our end of the year play). Pitt will be going up in the rankings since construction is about to begin on a new science tower that will bring a lot more research money and the dean is recruiting for a lot of new scientists. Also, the cancer center (which already has more oupatients than MD Anderson or Sloan Kettering)is almost complete and that will bring more research grants since it will free research space at the current science tower.
-USNews Pitt #17, Pritzker #19. I would take that with a grain of salt, in any case, pretty similar as seen by others around the country.
-Pitt has the hybrid lecture/PBL in the first two years. It's organ based, organized by blocks and the school makes sure that you have plenty of time to study for boards.
-3rd and 4th years. I don't know much about the hospitals at Chicago, but I think Pitt can compete with "almost" anyone. UPMC is a network of 19 hospitals, anything from tertiary centers (2 of them, Presbytarian, Shadyside) to community hospitals and we get to practice in any of them. Like Peds? Children's is ranked 4th. Like Ob-gyn, Magee's Hospital is ranked 10th. Like psych, Western Psych is ranked 11th. UPMC as a whole is ranked 15th so you'll be practicing and learning from some of the best in the country no matter what specialty. There's a new sports complex where the Steelers/Pitt train this is absolutely amazing and which brings athletes from all over the country to train/heal there. You will treat people from all over the country as well some from all over there world here at Pitt.
-Faculty/Staff are very encouraging and supportive. Students are amongst the frendliest and non-competitive (unless you plays sports!) Overall the feel is of cooperation and friendship.
-Future: Pitt/UPMC is embarking on a 700 million dlls construction that will see a new Children's hospital/new biomedical science tower/new outpatient tower/overall facelift to the Oakland UPMC campus. The hospitals are most profitable in all of Pennsylvania and UPMC is the only major med center in Pittsburgh and Pitt the only med school (no competition vs. 4-5 other med schools for patients, training sites, etc.)
If anything I don't think that Pitt gets enough recognition/credit from people since it doesn't have the name like Stanford/Pritzker/Vanderbilt. Granted Pitt has only been "good" for the last 15 years so it's reputation is not quite that strong/established yet.