In case you needed any proof that the No.1 activity on Facebook is goofing off, the chart above from Flowing Data shows the number of applications by category. About half of the 23, 160 applications on Facebook fall into the “Just for Fun” or “Gaming” categories. “Dating” and “Chat” are also high up the list. “Money,” “Classifieds,” and “File Sharing” are the least popular.

Facebook is a marketplace of sorts. It stands to reason that application developers are chasing the categories where they are a seeing the most usage. No surprises here, but a chart like this really drives the point home.