Well it's not the first phone to get FroYo, or even the first phone with HTC's Sense UI to receive the delicious update, but Froyo is coming to UK carrier O2's HTC Desire. The update hit the air - before being pulled almost immediately!
According to O2's full statement posted on their forums,
As some of you will have noticed the Android 2.2 Froyo update for HTC Desire on O2 went live this morning. While we’re pleased that so many of you have been able to download it successfully and are enjoying the benefits of 2.2, we have seen that a small number of people are having problems installing the update.