This new update has been done by Xda-Developers and it contains an update of OS to 2.1 for HTC Hero running on Sprint Network. This ROM is a test built for now but Zenulator expresses that the final version will be available soon too.
This ROM update requires rooted HTC Hero thus for those who do not know how to root the phone, head over here for a quick tutorial.
It is highly recommended to read through the entire post before proceeding to install the Android 2.1 ROM on HTC Hero as you might end up bricking your phone. Our usual disclaimer is in effect here, that is, in case something happens to phone or to yourself or thy neighbor in this process, don't blame us or in simpler words, "don't shoot the messenger".
Click to Download the HTC Hero Android 2.1 Customer ROM
Read the entire Post before proceeding.
Thanks to Blogs DNA for the update