BitTorrent-4.4.0.exe (setup file for Windows)
BitTorrent-4.4.0.zip (source code)

Benefits

• More compact interface
• Search bar removed (as I never use it)
• Advanced tab under Settings has been revealed
• Infohash and piece information revealed in Torrent Info window
• Improved queue system
• The number of peers and seeds (tracker totals in brackets, if known) and distributed copies are now shown, along with a BitTornado style share ratio
• The title (and tray icon) will tell you the combined upload and download rates
• Modified the code used to identify the max_incomplete value
• Various other tiny improvements

No, I'm not a fan of the new icons either (hence my icons in my version), but at least you can change them yourself by replacing the PNG files (see below)

Previous Version

BitTorrent-4.3.6-Beta.exe (setup file for Windows)
BitTorrent-4.3.6-Beta.zip (source code)

These should work with the latest official client, as well as my BitTorrent Mod.

NB: Some browsers may fail to display the PNG transparency correctly (IE7 Beta works, but previous versions don't)

Default (4.3.6 onwards)

New Classic (4.3.5)

Old Classic (4.3.x?)

iconpack.zip (default, new classic, old classic)

SilentBob v1

sbbtv1.zip (my first icon pack, status icons work slightly differently)

Installation
Close the BitTorrent client (you may need to check bittorrent.exe isn't running in Task Manager) and copy the PNG files from whichever folder you like and paste them over the top of the icons at C:\Program Files\BitTorrent\images\icons\default (or wherever you installed BitTorrent on your computer). When you start the client, it should use the new icons.