The Ubuntu Touch Developer Preview has been released. For the time being it is aimed for developers therefore it isn't something you should use in daily basis. Several features are missing such as playing music, no mobile data connection, PIN/PUK support, etc., and of course there are bugs.
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Just a few hours ago Canonical unveiled a new tablet running Ubuntu touch - the same OS running on Ubuntu phones. It will have multi user support and multitasking capabilities as well. Downloads for the Google Nexus 7 and Google Nexus 10 will become available along with Ubuntu Phone images on February 21st. Here is a screenshot of the new tablet and a couple of videos explaining its main features.
A video showing KDE Plasma Active running on a Nexus 7 tablet was published in YouTube. The UI looks choppy however it is very promising!
Valve's Steam Client for Linux is now officially available for Ubuntu 12.04 and Ubuntu 12.10 via Ubuntu Software Center. It is available for both 32bit and 64bit versions of Precise Pangolin and Quantal Quetzal.