I finally took some time yesterday to install Windows Mobile 6 free upgrade from HTC's website for my AT&T Branded 8525, otherwise known as the HTC TyTN. This upgrade is meant for all AT&T customers with 8525 only. The upgrade period is 11/1 to 2/1/2008, so you better act quick or atleast download a copy of the RUU Rom file and print out the instruction before 2/1.
The installation is relatively painless. I don't save a lot of personal information on my phone's main memory and I am in sync with my outlook with contacts and tasks so there wasn't anything to back up with. After I made my final synchronizations, I followed the instruction and installed the RUU effortlessly. The entire process took about 15 minutes.
Final thoughts: The new WM6 looks and performs better on the good ole' 8525. I noticed the phone reacts faster to menu selection and pull down. A general improvement in response rate. Previously running on WM5, I had a hard time getting the phone to "connect" to my computer. This problem went away however, took me a while to realize I had to turn off "advance USB" connection setting from the phone to get it to synchronize to my address book successfully. All in all, it was an easy upgrade from HTC. Kudos!