Welcome aboard, Anubis9! It's unlikely that your HD7 will have Mango, the 7.5 version of WP7. That's one of the original WP7 phones, and I'm guessing T-M -or any other source- has had that device in stock for a while. Expect to get update prompts when you connect, and hopefully, it will take you through all updates smoothly. Be sure you have the latest version of Zune installed (4.7) and good luck getting set up.