Microsoft's next push to make Windows Phone differentiated and relevant will revolve around deep integration with Skype. Skype, which Microsoft acquired in October, has a mediocre presence in the mobile space right now. It is not very welcome by the major carriers, which feel threatened by Skype's ability to place phone calls through data channels instead of the traditional mobile phone spectrum.
Microsoft is nevertheless pushing forward and hoping that by making Skype an integral part of its mobile experience, people will realize there's something unique and special about Windows Phone.
Had Windows Phone first launched five years ago, there's a good chance it would be the de facto mobile OS today.
That is to say there is nothing inherently wrong or missing when it comes to Microsoft's nascent operating system. However, it also doesn't really do much to stand out.
One of the biggest features in Windows Phone is the ability to connect to Xbox Live, earn achievement points that are presented in your Xbox 360 account profile, and chat with gaming friends even if you're thousands of miles from your game console.
However, there is a strong likelihood that Microsoft will bring the Xbox Live app to Android and iPhone users as well, which would eliminate what is perhaps Microsoft's most important exclusive feature in Windows Phone.
Since Microsoft owns Skype, the possibilities for integration there are very interesting so we'll have to see how this plays out.