This is just something that came to me earlier. Downloading maps can still be slow, even when on a fast server using cURL.
Since numerous players are likely to be downloading something at the same time, could a bittorrent style installation work for downloads?
since the question is could, the answer is yes. practical? no.
shared upload from several medium speed repos and all users uploading at say 10kbyte/s would slam an upload out "Really Fast" if it were configured right. the problem is that when there's a game full of ppl downloading 1 pak this isn't bittorrent's strength at all... small swarms downloading a small to medium file ( < 100mb), it would take most of the file to reach peak speed. so while it's possible, it's not practical.
I would think you could get much the same effect by having a list of repositories that are given out round-robin to ppl in game (reducing the number of ppl using one repo), or having a 'download manager' that could download from multiple configured sources at once without the bittorrent overhead. bittorrent is great for a multi-gigabyte file and hundreds of peers that aren't staring at a screen waiting for it to finish so they can play.