Actually, I would like to point out that at no point has anyone from HTC said the Hero will be getting updated to 2.1.
HTC tweeted "“The rumors are true! Hero will be getting an Eclair update. We ask for your patience as we update Sense for the fancy new Android OS.” back in October. That is the only offical word on the matter.
Although Google's Andy Rubin said "everyone will be getting Android 2.1 when it's open source" the Hero is not a google phone and they have no control over what updates it gets.
There is a common assumption that the Hero will get updated to 2.1 due to the leaked ROM's floating around, but I want to reiterate, incase they only update to 2.0 and there is some kind of mob uprising.
We have never been told the Hero will get 2.1, only that it will get Eclair.
EDIT: Although I have just seen Google have stated 2.1 is still Eclair, not Flan. Confusing no?