The popular cross-platform BitTorrent client Transmission, praised by its users for being full-featured but lightweight, is now officially the new default client for Ubuntu.

Transmission is already included in the 4th Alpha release of Hardy Heron, and is set to replace the Gnome BitTorrent client that Ubuntu has used up until now. A stable version of Ubuntu 8.04 is expected to be released in April 2008.

Transmission has gained a lot of popularity over the last year, and is considered to be one of the fastest and lightweight BitTorrent clients. It is an Open Source project, and the application is currently available on almost every operating system except Windows. Similar to uTorrent, it focuses on being lightweight, while including all the features a demanding BitTorrent user needs.

The Transmission team describes it as follows: “Transmission has been built from the ground up to be a lightweight, yet powerful BitTorrent client. Its simple, intuitive interface is designed to integrate tightly with whatever computing environment you choose to use. Transmission strikes a balance between providing useful functionality without feature bloat.”

Transmission uses little resources, and we’ve heard of people running it on their routers, NAS devices and even mobile phones. There is also a great WebUI for Transmission, called Clutch. With Clutch you can easily monitor and control your torrents remotely. Today, the Clutch team has released version 0.3, and instructions on how to get started are over here.

Downloads and more information about Ubuntu Hardy Heron can be found in the Ubuntu Wiki.