PubCon: Buying and Selling Links, Good or Bad?

The Linkfluence session at PubCon reportedly had a packed out house with many opinions. We already brought you Aaron Wall’s take on the infamous link buying subject, and now we’re going to delve into Rand Fishkin’s ideas on the subject.

Here’s the question that causes so much debate: Is link buying good or bad? Which is it?
If you are selling links and making money, then it seems to be working out “good” for you. Another scenario in which it seems to be “good” is when you are purchasing links and your ranking is improving.