The latest version of this security-oriented distro can be downloaded from Softpedia
Qubes, an open source operating system designed to provide strong security for desktop computing, which is based on Xen, X Window System, and Linux and can run most Linux applications and utilize most of the Linux drivers, is now at version 2 RC2 and it's ready for testing.The Qubes distribution was built as a virtual stronghold and it should be one of the most secure operating systems available right now. It's not a Linux distribution for beginners and it requires users to get informed before using it, but it's all worth it once you understand how it actually works.
The Qubes releases don't happen very often. In fact, the previous RC in the series was made available back in April and the development of the new branch actually started in 2013.
“Today we're release the second release candidate (rc2) for Qubes OS R2. There are currently no more open tickets for the final R2 release, and we hope that what we release today is stable enough and so will be identical, or nearly identical, to the final R2 ISO, which we plan to release after the summer holidays.”
“After Qubes rc1 release a few months ago we have been hit by a number of problems related to unreliable VM start-ups. The most prevalent problem has been traced down to an upstream bug in systemd, which just happened to be manifesting on Qubes OS due to specific conditions imposed by our startup scripts,” note the developers.
The devs are also working on a Debian template for Qubes AppVMs, which can be installed with a simple command. It features GUI virtualization, secure clipboard, secure file copy, and other integration features, all of them working out of the box.
Also, a “minimal” Fedora-based template can now be found in the Templates Appstore, the Wiki server has been moved to a bigger EC2 instance, and a number of themes for installer and plymouth have been provided by default.
Keep in mind that, unlike the rest of Qubes, which is distributed under a GPL v2 license, the Qubes Windows Support Tools are not open sourced and are distributed as binaries only, under a proprietary license.
Check out the official announcement for a complete list of updates and upgrade instructions.
You can download Qubes 2 RC 2 right now from Softpedia. Remember that this is a development version and it should NOT be installed on production machines. It is intended for testing purposes only.