Bit Torrent for Mozilla Firefox
 

application/x-bittorrent; /usr/bin/btdownloadgui.py %s; test=test -n "$DISPLAY"

I want Mozilla Firefox to recognize application/x-bittorrent. Will having the above in mailcap be sufficient?

give it a go, and see what happens. i like downloading the torrents to my hd and running them from there, though, so you dont have to go back to the webpage to resume.