T-Mobile has released an update for the HD2 so now we went from 2.13.531.1 to 3.14.531.1. I haven't had any issues with it so far. It seems very stable and fast. The update procedure was VERY easy and comes with a Read me file for perfect instructions. It said it would take about 10 minutes to do it and it only took about 3 minutes. Only 2 things you must remember when updating to 3.14.531.1.
First is backup all contacts, pictures on the phone storage or anything else stored on the phone then you must Remove the SD card. Since its a windows phone the SD card is "plug and play" so you can remove it while the phone is on.
REMEMBER all of the data on the phone will be erased (just like if you did a Master/ factory reset) so back it all up then pop the SD card out.
This link will show you how to perform the update
AND
This link will take you to the update page. Just click the "Get software" button and go from there.
If you keep getting redirected to the HTC.com website when you click the download button after entering your IMEI number then turn off any popup blockers in IE or nortons firewall ect.