http://thenextweb.com/microsoft/2013...rade-to-skype/

So, what’s happening between now and 15th March?
Messenger will continue to work as you know it today. If you are signed in with Messenger on your desktop** you will see a banner notification to upgrade. When you click on the banner, an installer window will open with the request to upgrade. This will take you through our installer flow to install Skype and automatically uninstall Messenger.

So, what’s happening after 15th March?
Messenger users on desktops** will not be able to sign in and will only be able to upgrade to Skype. If you attempt to sign in, a notification will appear, and if you continue, you will be taken through our installer flow to install Skype and automatically uninstall Messenger at the same time.
PS: I heard that M$ bought Skype for $8.5billion ... Idiots... I downloaded it for free