Rob Church wrote:
I would guess that image dumps stopped being provided due to file sizes and bandwidth needed for distribution. There have been relatively recent discussions about providing BitTorrents for this sort of thing, to take advantage of all the benefits from those sorts of things, but no concrete plans have come to fruition (that I can recall or am aware of at this time)..."watch this space" might be good advice.
Proabably a system like jigdo http://atterer.net/jigdo/ performs better. I doubt the peer to peer can help in sharing full tars. If each image is shared individually... might help a bit.