There are people on SDN who posted in previous threads and who I know in real life who got a ton of interviews at cali/nyc/boston programs, hopkins, duke, MIR, etc... but for some reason Mayo, Michigan, CCF are more regionally selective. Know someone who matched UCSF and got all the top interviews but struck out completely in the midwest (CCF, Mayo, Michigan, Northwestern, Chicago) with the exception of MIR. Other examples can be found in the Radiology 2011 applicants SDN thread. If you look at the UM class profile like 3/4 come from Michigan or Wayne State and many have ties. Thus, I think there may be an element of programs feeling like you might not come there if you're from a top med school on the east or west coast and have the raw numbers/ application elements or otherwise a top applicant with no direct ties. Dr. TLM on AuntMinnie has alluded to this before though I cannot confirm if it is a major factor, but it seems the only potential explanation for why some applicants get some of the most competitive interviews but then are denied in Cleveland, Rochester, +/- Ann Arbor other than iterative randomness.
I would be interested in Michigan for personal reasons though I have no direct ties, which makes this unfortunate in my case, regardless of all my rationalization.