After having officially announced its forthcoming “Windows Phone 7 Series” platform at the Mobile World Congress event last week, Microsoft has earmarked its March-scheduled MIX event in Las Vegas for disclosing the details about the developers’ avenues on the new platform.

However, in the interim, some unofficial leaks, probably from Microsoft’s OEM partners, about the Windows Phone 7 Series have revealed that development on the platform will essentially rely on managed code. As per the buzz, developers will be able to write their apps in two frameworks - one based on Microsoft’s cross-platform .NET environment, ‘Silverlight;’ and the other based on its XNA gaming platform.

One of the document leaks about Windows Phone 7 Series read thus: “In addition to the standard Windows Phone Application Platform that will be publicly available to all developers, partner applications will have access to an extended set of managed APIs and a limited set of native APIs. The extended managed APIs are meant to support extending the phone experience with functionality that is specific to a phone or network.”

Further noting that the new Microsoft platform will support the “3 Screens (Phone, PC, TV) + the Cloud” world, the leaked documents also highlight the inclusion of Microsoft’s ‘Visual Studio 2010’ and ‘Expression Blend’ features that will help developers design and create “compelling” user interfaces.