The market for Mac torrent clients has been expanding quite a bit recently, and Torrentfreak has a nice review of a new beta version of Transmission, a long-standing favorite of many a Mac torrenter. While the review rounds up many of the nice new features, I'll give you the cliff notes for the slackers in the crowd: "Transmission 0.7 Beta is by far the fastest, most light-weight and one of the most appealing BitTorrent clients for the Mac."
Diving further in, some of Transmission's new features seem to be inspired by Xtorrent, a new beta client from Dave Watanabe (of NewsFire fame). Of these new features, notables include time-of-day based speed limits (i.e. - slow down my torrent downloads while I'm at my desk at work from 9-5), as well as a Watch Folder with automatic cleanup of your torrent files (again, very Xtorrent inspired). The idea is: most Mac browsers by default download all files to the desktop, but that might not be where torrent users want to keep their downloads as well. This Watch Folder allows Transmission to automatically snag any torrent files you download to the desktop, move them to a user-specified folder and begin the torrent download. Ah, software automation - it's a beautiful thing.
Check out the rest of Torrentfreak's review, as plenty more is packed under the hood of this new beta.