Perhaps it's due to the recent legal battles by the music industry - but peer-to-peer networks are showing a huge decline in music swapping.

CacheLogic reports that 62 percent of the traffic on major P2P systems BitTorrent, eDonkey, Fastrack and Gnutella are video content.

Music is just at 11 percent with the other 27 percent going to games and software.

Sixty five percent of all audio files by volume of traffic are still traded in the MP3 format, but a surprising 12.3 percent are in the open-source OGG file format (almost all exclusively traded on the BitTorrent network, particularly in Asia)

The study also showed BitTorrent is increasingly being used for the distribution of legitimate content.