i'm not in a detroit area residency, but i was born and raised in metro detroit, and lived in ann arbor for 6 years. i have the following opinion....
I wouldn't live in ann arbor if i was planning on working in detroit. ann arbor to downtown detroit (i.e. Henry Ford, DRH) is pushing an hour commute, despite what others say. Sinai-Grace may be in the 45 minute range. Plus, if there is an accident or incliment weather, you're looking at even longer.
now this begs the question, why would you want to live so far away? do you have a sig other or something in ann arbor?
i know of plenty of couples where one matched at UM and the other downtown. they tend to live in canton, livonia, plymouth, etc. they're basically midpoint between the two towns with easy freeway access along the M-14, I-275, I-96 corridor.
and a general opinion on commuting...i hate it. i live 12 minutes from my hospital and its too long sometimes. time spent in the car, even if its spent decompressing or listening to EMRAP or whatever, is not as good spent at home or actually doing something. i think anything longer than 20 minutes just ain't worth it.