With already many devices gearing up to have Microsoft's next mobile OS incarnation, it was time to release the Software Developer Took Kit. It's available for download right now and offered in over a half dozen languages. Current developers for WM 6.1 will jump in easily with WM 6.5 – almost having similar codings. One thing that really stands out is that it includes APIs for gestures like the flicking and scrolling. Finally, there are separate builds for both Windows Mobile Professional and Standard editions.