I called Tmobile to see what are my options to upgrade to the HD7 but still keep my tzones. The Rep told me I had to signup for the $30 plan and that tzones will not work with the HD7. I told the Rep that I have a friend that has the HD7 and tzones is working, and the Rep said that by Sunday it will be blocked. The Rep also told me to call in about two weeks because of the new cheaper data plans will be out and I can upgrade to the HD7 with the cheaper data plan.
If I don't get the HD7, I'll be waiting for the next batch of WP7 phones that will be 4G, FFC, and a higher resolution screen or SAMOLED.