BitTorrent hadn't seen a major update in about two years, but that was before it bought out uTorrent. Now, adopting its new sibling's interface has completely reinvigorated the original BitTorrent client.
Previously, BT had lacked features that other torrent innovators had spent time testing and investing in. Now, in one fell swoop, BT has access to everything it lacked. You can pick which files in a torrent you want to download, throttle your Internet connection to suit your whims, muck about with the Web UI and, basically, do everything that uTorrent can do.
There's an RSS tracker and search bar, just like in uTorrent, but there's where we encounter one key difference. Where uTorrent's search takes you to the MiniNova torrent site, BitTorrent's goes to BitTorrent.com, a pay-for-most-content site. There's also a menu bar item in the BitTorrent client called Get Stuff, with links to Movies, TV, Music, and Games at the BitTorrent content site.
Without a doubt, BitTorrent has taken drastic steps to reverse course and unsink its sinking ship. Although BT still eats more memory than its new sibling, it's hogging significantly less than before. The install file reflects the new code, shrinking from nearly 6MB for version 5 to less than 1MB for version 6.
BT also comes with a small piece of software called DNA. The BT site calls it protocol for "Delivery Network Acceleration," but beyond a nebulous description, it's hard to tell what exactly it does.