They starting enforcing this back in Australia about 8-9 years ago, and I LOVED it. So many a-holes would cruize in the left lane thinking "F you" to everyone trying to pass.
Once the $100 tickets started flying. EVERYONE stayed right unless they were passing or making a left turn within the next few hundred meters.
I'm praying to God, Allah, Budha, Moses and the Giant Rainbow Serpent, that they enforce this in MI - the state legendary for left lane, self-proclaimed, speed-enforcers. So many pricks on the expressway will stay in the left lane regardlesss of the speed they're doing refusing to get over even if it's open - despite all the honking flashing and bird-flashing you give them. And then they have the ordacity to give you dirty looks when you pass them on the right (and cut them off for good measure!

) Fuggers!