I think one thing that has been kept companies from leaving is the production value of a Wisconsinite vs. people in some states. I'm not saying that we are the only state that produces quality labor, but there are other states that do far worse.
But you are right, with the tax incentives to move elsewhere, it is hard to imagine companies staying in our state for much longer.
"There are two parties in politics: Republicans and Democrats. Republicans have bad ideas, Democrats have no ideas." - Lewis Black