Earlier posts in this thread say that the technique works with the HTC Faraday (Cingular 2125) ... I presume that the way to do it is to follow the instructions for the HTC Tornado? Can anyone confirm that?
Also, what important settings will I lose and need to re-enter? I know I'll lose Exchange server synch settings, but I know how to re-enter those. I know I'll lose contacts, email, etc.; no biggie there because I'll just fetch it all again from the Exchange server. But what about the various settings (about which I know absolutely nothing) that tell the phone how to connect to the ATT network? Are those settings safely located on the SIM? Or will I need to re-enter them?
 Okay, I went ahead and did it. For anyone else who is wondering: yes, you follow exactly the directions for HTC Tornado. No, you will not lose your phone network settings (I guess they're on the SIM). Yes, you will lose your data network settings; I found instructions for re-entering AT&T settings here. Nitro's WM6 rocks; I can't wait for a stable WM6.1 to try!! [/edit]