Limewire gets improved torrent support in new beta thanks to LibTorrent
By adding LibTorrent to the mix, Limewire now includes the engine powering such apps as Halite, Deluge, Miro, Free Download Manager, and more. As a result, the new version gains support for IPv6, Mainline DHT, UDP tracking and HTTP seeding, local peer discovery, and peer exchange (PEX).
Interestingly, being the most widely-installed app doesn't translate into actual use. As TorrentFreak points out, in a survey of nearly 200,000 bittorrent peers only 43 were using Limewire.
Why so few? Limewire users are generally only after the its Gnutella downloading abilities, though as torrenting become more mainstream the program will no doubt be an attractive option for the average user.