Throwing N-bombs around and singing a different song are two totally different lapses in judgement.
However, I never thought what Imus did was really bad in the first place. I also think that the station managers that decided to pull the plug on him were perfectly in their right. Just because you can say something, doesn't mean there aren't consequences.
Of course, I've always been for business owners having the whole "freedom of association" right. Go figure.