Microsoft used its Professional Developers Conference 2010 this week to promote the cross-platform opportunity it offers developers, stating that “many of the same skills, languages and tools used to develop cloud applications on [cloud platform] Windows Azure have come to Windows Phone for apps and games.” The company reiterated that the Windows Phone Marketplace will launch with “more than 1,000 quality games and applications that extend the unique user interface and functionality of Windows Phone 7,” and that the store will be open for application submissions from 3 November 2010. Steve Ballmer, CEO of Microsoft, asserted: “there has never been a better time for developers to bet on Microsoft.”

At the event, in addition to the high-profile keynotes, the company held a number of tutorial sessions, with topics including optimising Silverlight apps for Windows Phone devices, developing XNA-based games for handsets, and the lessons Microsoft has learned while helping its initial partners bring apps to customers.

On the Windows Phone Developer Blog, it was noted that “if you know Silverlight you are in pretty good shape, but you need to get up to speed (and quickly) on the “phone stuff”.” The event also discussed the Metro graphics language which underpins the Windows Phone user experience and how to optimise third party apps to work with this – although it was also noted that “if your application doesn’t fit into Metro, don’t jeopardise your application experience…use Metro where appropriate, and remember that you can build a completely different experience if you think it better serves your application.”

Microsoft has also published some ‘minor revisions’ to its Marketplace policies, although it did not detail what these entail. The company published a set of guidelines in September 2010, listing a number of issues that could prevent apps from being listed in the store.