Even though the CTP (Community Technology Preview) has been out for some time now, the official Beta of the Windows Phone 7 developer tools have just been released. The tools include (quote):

• Visual Studio 2010 Express for Windows Phone
• Windows Phone Emulator
• Silverlight for Windows Phone
• XNA Game Studio 4.0 Beta
• Expression Blend 4 for Windows Phone Beta

Hopefully, with these tools being available, and the hype about the platform, we will see a great success of the Windows Marketplace on Windows Phone 7, coming this Fall.

Get them here: http://www.microsoft.com/express/Phone/