Unions have their place. Forcing people to pay union dues is wrong, though. And the Employee Free Choice Act that was floated around was wrong.
Just like any organization it has good points and bad. I wouldn't want unions to get everything they ask for, because it would never be enough. And I wouldn't want to see them go away.
I don't see what's wrong with what happened in Michigan. The unions should do a better job of selling themselves to potential members if they're concerned about people not paying dues.