That is one awful article. Arbitrarily cut in 4 pieces and never getting to the point. It is about a paper: http://conferences.sigcomm.org/co-next/2010/CoNEXT_papers/11... [pdf] which from a first glance is not very good either.

Also the traffic is not what this is about but users uploading things.

Did anyone read the paper? Worth a second look or is it rubbish? "We demonstrate that a small fraction of publishers is responsible for 67% of the published content and 75% of the downloads." suggest the ladder. Not to mention that they talk about Bittorrent but actually mean The Pirate Bay.