uTorrent for Mac OS X - beta release
As stated uTorrent Mac OS X 10.5 is in beta release, "This is beta software, and may contain serious bugs. We think it's stable enough to share and hope your feedback will help us improve it."
The release currently runs on Leopard/Intel Macs.
uTorrent released in the net in September 2005, and soon became the most widely used BitTorrent application.
You can download the uTorrent Mac version in this link.