This was achieved by offering free video calling through an easy to use app which is available on multiple platforms. A Mac user can call a Windows user and then the Windows user can phone another friend who's out and about with their smartphone.
Microsoft are encouraging you to merge your contacts into one Skype service. They are emailing customers with the following:
Having tried out the merging process I can report that it was surprisingly easy. Just download the latest version of Skype for your operating system. Log in using your Microsoft (MSN) account. Choose 'I already have a Skype account' and sign in with that account. Click 'Merge Accounts' and you are done.
Starting April 8th, we will begin upgrading customers from Messenger to Skype. The process will take a few weeks to complete. April 8th is the first day you may be required to upgrade. This is a bit later than the March 15th date we previously mentioned to some of you as we wanted to give you more time to make the transition.
All of your existing Messenger contacts are in a separate list and you can instant message them from within Skype itself. By linking your Facebook account too you can use Skype to contact Facebook friends using Facebook Messenger. Facebook is also cross-platform so they can be in a web browser on the Facebook website or using the various Facebook Messenger apps for iPhone, Android etc.
With the new version of Skype comes a slightly darker shade of blue for the logo which is simplified to reduce the 3D effect which it previously had. The simple bold logo fits more with Microsofts branding in Windows 8 and it's services such as Outlook.com.