As you already know HTC has introduced three phones – Desire, Legend and HD mini- at the Mobile World Congress (MWC 2010) in Barcelona.
One of the most powerful smartphones HTC Desire is based on Google Android 2.1 and uses the proprietary Sense user interface. The phone has the same hardware as HTC Nexus One and that’s why enthusiasts tried to install the ROM of HTC Desire on it. The file was too large for the memory of Nexus One, so it had to be cut, but eventually the developers turned to tighten the shell of Sense on Nexus One.
The proof is on the photo. More info available at XDA-Developers