This latest edition consists primarily of bug-fixes. Microsoft/Skype software engineer, Marco Cimmino, wrote: "Not only did we conquer the navigation issues and bugs from previous releases, but we increased the stability when logging in from a Microsoft Account. There are also greater efficiencies, such as not having to re-type your password when entering via 'My Account' if you are already logged-in with the client. Voice messaging is optimized for ease of use and is now just one click away from the options window."
Installing Skype on Linux is very straight-forward. Microsoft provides detailed instructions for most popular Linux distributions including, CentOS, Debian, Fedora, openSUSE, and Ubuntu. Many Linux distributions are also now including Skype in their software stores.
For example, I installed my copy and the 4.2 update, via Linux Mint 15's Software Manager. That said, 64-bit Debian, Ubuntu, and related distributions may need to install the libasound2-plugins:i386 package for audio support. In my case, I didn't need to install this.
Skype video-support, however, can be tricky. If you're finding you have trouble getting your Webcam to work with Skype, see this Linux Mint community posting, How to make Webcam compatible with Skype.