HTC's UK Facebook page posted an announcement stating that they have not been able to make the upgrade to Android 2.3 work with the internal memory on the HTC Desire with HTC Sense. They also state, "We're sincerely sorry for the disappointment that this news may bring to some of you."
Update 06/16/11 @ 1:20pm : HTC has posted to its Facebook page that will update the HTC Desire, removing some apps.
Owners of the discontinued T-Mobile G2, which is now discounted to $49.99 at Amazon.com, have received email notifications that HTC will update the T-Mobile G2 to Android 2.3 Gingerbread with some extra features, including a 3G/4G vs. “H” signal indicator. A T-Mobile data plan is required for the update.
There is no release date yet for the update. The list of features in Android 2.3 Gingerbread update are impressive, with the addition of download manager, active app management, shortcuts, one-touch copy/paste, widgets, icons, app groups, updated calendar options, camera geotagging, improved email synching, and camera auto-focus improvements.