Not really. Similar purpose, but it is not embedded in the network (every intermediate hop could support a layer of cache, from backbone providers down to consumer routers).

Note that Bittorrent is at least twice as inefficient as this scheme - every peer request requires the content go "up" and then "down" to the peer - through several intermediate hops.

This scheme, the data travels along the same path as the original content - it just doesn't ask for the same copy of the content over and over again from the source.