The article later notes Skype had 663 million registered users, as of a recent filing
The acquisition would be Microsoft’s largest ever and it is the software giant’s effort to gain a foothold in the world of voice and video communications. Microsoft would be able leverage Skype’s more than 600 million registered users into using its other products. For example, it could be connected to Microsoft’s Xbox 360 and Kinect systems, and integrated into the company’s flagship product, Office, as a way for business users to better collaborate.
It could also help Bing, its search engine, which competes with Google. It may also help bolster Microsoft’s fledging mobile telephone offering, which lags far behind Apple’s iOS and Google’s Android operating systems.