Microsoft has announced that it plans to 'retire' its instant messenger client Messenger Live, and shift all its users to Skype.
Microsoft bought Skype in May last year, paying $8.5 billion, and has been working towards a changeover ever since.
Now, it's announced a tight timetable, with all users outside mainland China set to switch during the first quarter next year.
"By updating to Skype, Messenger users can instant message and video call their Messenger friends," says Skype president Tony Bates in a blog post.
"This effort started with the release of Skype 6.0 for Mac and Windows a few weeks ago, which allows you to sign into Skype using a Microsoft account. Now Messenger users just need to update to the latest version of Skype, sign in using a Microsoft account, and their Messenger contacts will be there."
He promises broader device support for all platforms, including iPad and Android tablets, along with instant messaging, screen sharing, the ability to call landlines and video calling, including group calls.
The speed of the transition has taken some by surprise, and many users are concerned. Some features, such as 'nudge', remote assistance and games look like they'll no longer be available.
There's always the danger that some users will switch to another service instead, such as WhatsApp Messenger or Google Talk. If everbody moves over, though, the merger will boost Skype's users by a third.