The use of indirect evidence as "proof" of downloads is known, the interesting bit here is that in spite of pushback from ISPs and users, industry practices have not changed.
Perhaps this (and the widespread lack of privacy in cloud-based services generally) will drive more users to privacy-preserving data sharing options, such as OneSwarm.
sertsa writes: "Earlier this year a group of researchers at the University of Washington came up with a scheme to use peer-to-peer networks to store and ultimately forget the keys for encrypted messages causing them to "Vanish". Now a group from researchers from the University of Michigan has come up with a way to break this approach.
In our experiments with Unvanish, we have shown that it is possible to make Vanish messages reappear long after they should have disappeared nearly 100 percent of the time . . ."
CSEMike writes: "Currently popular peer-to-peer networks suffer from a lack of privacy. For applications like BitTorrent or Gnutella, sharing a file means exposing your behavior to anyone interested in monitoring it. OneSwarm is a new file sharing application developed by researchers at the University of Washington that improves privacy in peer-to-peer networks. Instead of communicating directly, sharing in OneSwarm is friend-to-friend; senders and receivers exchange data using multiple intermediaries in an overlay mesh. OneSwarm is built on (and backwards compatible with) BitTorrent, but includes numerous extensions to improve privacy while providing good performance: point-to-point encryption using SSL, source-address rewriting, and multi-path and multi-source downloading. Clients and source are available for Linux, Mac OS X, and Windows."