I once had the opportunity to see Charles Petzold back in 2005 at the NYC .Net User Group, when he gave his infamous "Does Visual Studio Rot The Mind" talk:

Abstract: Visual Studio can be one of the programmer's best friends, but over the years it has become increasingly pushy, domineering, and suffering from unsettling control issues. Should we just surrender to Visual Studio's insistence on writing our code for us? Or is Visual Studio sapping our programming intelligence rather than augmenting it? This talk dissects the code generated by Visual Studio; analyzes the appalling programming practices it perpetuates; rhapsodizes about the joys, frustrations, and satisfactions of unassisted coding; and speculates about the radical changes that Avalon will bring.
- Charles Petzold

Go back and read the whole thing, or add it to your Instapaper, or whatever -- I'll wait.

OK.  Now that you're back having read that, or if you're already well aware of Mr. Petzold, thank you very much, and would like me to get one with it, here we go.

This book is a gift from the Windows Phone 7 team at Microsoft to the programming community, and I am proud to have been a part of it. Within the pages that follow, I show you the basics of writing applications for Windows Phone 7 using the C# programming language with the Silverlight and XNA 2D frameworks.

Yes, Programming Windows Phone 7 is truly a free download, but for those readers who still love paper—as I certainly do—this book will also be available (for sale) divided into two fully-indexed print editions: Microsoft Silverlight Programming for Windows Phone 7 and Microsoft XNA Framework Programming for Windows Phone 7. [Note from Devon: we should have these ready for order in December 2010.]

- Charles Petzold