If you have a 722, your software should be "turbo'd" as mine shows when the screen saver is on. That provides access to the 1080p VOD. My 622 however, is "not" turbo'd".
I think there is confusion about the terms. You can certainly subscribe to HD packages; unclear to me if you can subscribe, as an existing customer, to an HD-only package (which is what I think the previous post was referring to).
A current customer is grandfathered to the HD channel choice made prior to 8/01. CAUTION: Before any change is made to that choice, whether it be basic or HD packages, make sure that those changes, which will remove the grandfathered cost, result in a better plan. Eg. prior to 8/01 top 200 DVR ADV/with HD essentials, 722 phone connected, $59.99. No price change after 8/01. HD Absolute prior to 8/01 received ALL HD channels that were available for $29.99, +$5.98 DVR fee, +$5 locals= $40.97. After 7/31, Turbo Platinum DVR Adv went to $59.99 for the same HD services. Obviously, the grandfathered accounts are better when it comes to HD only service packs.