Yes, I concur it will charge on the PC. However, I've had a few inexplicable instances where even though the mogul thought it was charging, it was not. Yellow light on, voice command gave battery level and said "....and charging". Weird.
I just picked up a couple of these cradles on ebay. Has both USB and DC transformer, so it will allegedly charge on either. I have one for the desk and one for the car. Makes it easier to view on the desk/dash, also. Also has a place to charge a standalone battery, if you have one. A little more more pricey at $20, but I recommend.
http://cgi.ebay.com/USB-Cradle-Charg...QQcmdZViewItem