If you’re a developer who has experience with .NET, Silverlight or XNA, you already have the core skills necessary to start writing a Windows Phone 7 application or game. 

Since the Windows Phone 7 application platform is Silverlight-based, most articles or information about writing a great Silverlight application is also relevant to the phone.  The same is true for XNA articles and information for building games.

Below are some Windows Phone 7 specific links to help get you started: