It's almost never mentioned. I'm actually from Ann Arbor (ugh I know) and people just don't talk about college hockey with the exception of a very few. I'd say media coverage in the metro detroit area ranks like this- Lions, Umich football, Wings / Tigers, Pistons, Umich Basketball (only if they are good) Professional golf, then college hockey, but only if something big happens. Honestly, most of the people who just watched the basketball game last night won't even know Michgan is in the frozen four.
One example I think about alot is the night Michigan played duluth for the title in, 2011? I had an evening beer league game and a guy on our team was wearing a Umich hockey shirt. I asked why he wasn't watching the game and he asked "what game?".