Android Guys just broke this story that includes a letter from HTC to a customer asking about 1.6 upgrades in Europe for the HERO. Here is the response:Dear HTC customer, Thank you for contacting our Customer Center. We are dedicated to providing you with the best quality service and answering all of your questions and concerns. The Hero will not be receiving the Android 1.6 upgrade, it will however get the 2.0 one. Do note however that we do not have a confirmed release date for this upgrade all I can recommend at the moment is that you keep yourself updated by visiting our website regularly as the latest information will be available to view from there. Best regards, HTC customer support team HTC Corp. Global Service Division I would imagine the same will go for the US. LINK: European HTC Hero Skipping 1.6 Update | AndroidGuys
That tallys up with what I heard as the Sense UI apparently has all the bits for the Hero to make the jump to Eclair, where as vanilla android sets needed Donut to prepare for Eclair (hope that makes sense).
The only other worry I've heard around the horn, is that Sprint might not push the firmware update for the HERO. I can't really believe Sprint would block HTC's upgrade to 2.0, especially since this phone will be less than a year old (and less than 4 months old on Sprint). So, I guess I just need to learn some patience and wait quietly.
Here is their official video with a good demo on this feature at around the 1:00 mark. Enjoy. YouTube - Android 2.0 Official Video