The next version of Windows Phone will be called Mango or Windows Phone 7.5 according to the official Windows Phone website that has been updated recently by Microsoft.
The site, which can be found here, is an essential resource centre for developers working with Microsoft, who would only confirm Mango's expected release date as arriving "later in 2011".
Microsoft also announced that the company will drop the "7" version reference in the product's title which means that it will now be referred to, simply, as Windows Phone.
Amongst the enhancements introduced by Mango are multitasking improvements, updated developer tools (which will be available in May) and new capabilities for Marketplace.
Microsoft noted that the new features will enable Live agents to create "superior customer engagement" with real-time integration.
Developers will also have access to the Motion sensor library and the camera which paves the way for even more immersive augmented reality experiences.
We know that Mango will come with IE9 and will power the second generation of Windows Phone handsets that should come to the market in the second half of the year.
There are less than a dozen Windows Phone 7 handsets on the market; the HTC 7 Mozart, the HTC 7 Pro, HTC 7 Trophy, HTC HD7, LG Optimus 7, Samsung Omnia 7 and Dell Venue Pro.