HTC have confirmed that they're workong on an Android 2.0 update for the owners of the HTC Hero handset.
Here's what they said:
"Yes, we are working on an Eclair update for the HTC Hero. Because Eclair is a significantly enhanced release, it will require some time to update Sense for this new version of the Android OS. Please be patient while we work to provide you with a tightly integrated experience like the one you are already enjoying on your Hero."
The company will be bringing the update to all versions of Hero, but it's up to carriers to decide when and how to release it. There was no word on similar updates for Dream and Magic handsets, so for now we'll have to wait for a good port by xda-developers.