We've received a number of inquiries regarding a Windows Mobile version of the 1337pwn XBOX Live Friends List. The simplified browser version available here works fine on Windows Mobile.
Enter the following URL into your Windows Mobile device:
http://1337pwn.com/mobile.php
(Be sure to bookmark it after entering your friends)
It's nowhere as slick as the iPhone version, but it gets the job done. If you're running Skyfire, we've heard reports that the iPhone version runs like a champ in that browser.
At this time, we're not developing a native Windows Mobile application, but we might be persuaded given sufficient demand.
Thank you all for your feedback and support.