I got the comm error several times mentioned in the upgrade guide - it warns against disconnecting the usb cable during the upgrade process. My phone was connected and I got the screen that shows the current version and the version(s) to upgrade to (radio stack, etc). - It started the upgrade and my phone said "USB version 1.0" in big letters and then my my laptop did the USB disconnect sound and a message stating a USB device was not functioning. I tried a soft reset on the phone with the cable attached and it would not reset. I then unplugged the usb cable and slowly plugged it back in. My laptop then recognized a new USB device as mobile phone and I launched the installer again. It says the upgrade is a 3 stage process and can take 20 minutes. Right now it is at 71% of stage 1 for the radio stack. Fortunately I got a replacement XV6700 from Verizon yesterday for a minor issue so I am trying this on the original phone before attempting on the new.......radio stack completed after about 5-7 minutes and extended rom completed in about 20 seconds....now on stage 3 extended rom image update. Incidentally, your backlight on your phone is disabled during the upgrade and it is kind of hard to see that it is doing something. 3rd stage completed in about 3-4 minutes and now rebooting - ROM looks good 2.07!

If you don't want the Verizon customizations, remember to reset your device within 3 seconds after you calibrate the screen and to the riduculous cut paste operation for Windows Mobile 5 setup!