Update: Owners of unlocked Desires around Europe (and for that matter, the world) have informed us that OTA Froyo is being dished out in earnest. Enjoy!
"The Android 2.2 (FroYo) update for HTC Desire will start rolling out across Europe this weekend. As well as including the complete set of Android 2.2 features, the update will contain a few special additions of our own through the latest iteration of HTC Sense. The update will provide 720p video capture, HTC's App Share widget, as well as our enhanced HTC Caller ID, and improved multi-language keyboard. Also, through the update, HTC Sync will allow HTC Desire users to sync their music with iTunes.
HTC Desire users will be notified that the over-the-air update is available to download when their phone automatically checks for software updates. The update won't delete any of the phone's content. However, due to the size of the update, we would advise using a WiFi connection to download it wherever possible to avoid additional data charges.
This update will initially roll out to unlocked HTC Desire handsets. Operator specific versions of the update are undergoing testing and we expect to make them available in several weeks' time."