As of June 17, HTC HD2 users from the UK on O2 can apply a ROM Update which just surfaced on HTC’s UK support website.
According to the description, the version number is 184.108.40.206 and it is for O2 only but as we’ve got used to things by now, there’s no list of changes but the ambiguous marketing description letting us know “an updated ROM is now available for HTC HD2 (O2) users to download. As always, HTC is committed to providing customers with the best possible mobile experience”.
Note: Updating your ROM deletes all information on your device! Make sure to back up your sensitive data before updating.