Valve News #1:
This article brings two Valve news in one (article).

As you may know, Valve makes gaming on Linux possible via Steam. Steam gets updated to a new Beta version (again in a short time), coming with various fixes for Linux. Valve has the tradition to make Steam stable, as soon as it gets enough changes.
List of changes, brought by the Steam Beta version (from the official site):
- Fix overlay crash on non-Steam app shutdown.
- Big Picture mode store can show Linux support icons.
- Fix Steam crash on systems with no USB support.
- Fix game shortcut names for games with non-ASCII letters in the name.
- Fix some Big Picture crashes playing YouTube videos.
- Improve Steam client support for XFS and large drives.
- Fixed web browsing while in offline mode to load the proper offline mode page
For a full list of fixes, see the official site, I have liked earlier.
Valve News #2:
Half-Life, the game developed in 1998 has been finally updated for the Linux platform, by its Beta version.
List of improvements, from here:
- Added support for a crcclientdll key in liblist.gam to turn client.dll crc checking back on, useful for 3rd party mods
- Make sure the Close button has keyboard focus when you see the disconnection dialog
- Made the play command obey speak_enabled cvar
- Door movement sound fixes, make sure you stop playing the moving sound if you get disrupted
- Fixed crash if you hit retry while in control of a func_tank
- Fixed sprays not loading from the correct path causing them not to update
- Fixed a crash if you started a local multiplayer game, disconnected and then loaded a save game
If you need help the Steam installation on Ubuntu, Linux Mint or Fedora, see the following two articles.
- Instructions for installing Steam on Ubuntu / Linux Mint
- Instructions for installing Steam on Fedora
As a reminder, Dota 2 has been also ported to Steam on Linux. For more information, see this article.