The next major version of Ubuntu Linux isn't due out until October 29th. But the neat thing about open source projects is that development happens in public, and anyone willing to risk tackling a few bugs is welcome to download the recently released Ubuntu 9.10 Karmic Koala Alpha 3.

The latest build features a number of updates including updated versions of the GNOME desktop environment and the Linux kernel. Canonical has also updated the GRUB bootloader to GRUB2, changed the default filesystem to ext4, and added a new Intel video driver architecture. Ubuntu 9.10 Alpha 3 also replaced Pidgin as the default instant messaging client with Empathy.

Kubuntu 9.10 Alpha 3 is also available for download. Kubuntu is based on Ubuntu, but uses the KDE desktop environment instead of GNOME. This is the first version of Kubuntu to come with a netbook-optimized version optimized for devices with small screens and slower processors. Right now, most of the changes are in fonts and desktop settings.

The latest version of Kubuntu also includes the Arora web browser and updated versions of the Amarok music player and K3b CD and DVD creator. It also includes a handful of KDE widgets for social networks including Twitter, Facebook, and identi.ca.

These are still early releases and there are a number of known issues, including the fact that Windows may not show up in the GRUB boot menu if you install Ubuntu 9.10 Alpha 3 on a computer already running Windows.