Windows Phone Developer Tools are released! Install from here. You just need a Windows Vista or Windows 7 machine to start building apps and cash in on the next wave of mobile technology!
Read about the details and a recent ScottGu/CharlieK event here.
Additionally, the Silverlight team have dropped a good bag over on CodePlex – More controls for your Windows Phone 7 SL projects including Date Picker, Time Picker, Wrap Panel and more :-)
Get building those apps – be amongst the first to deliver a Windows Phone 7 application!