Due to AMOLED display panel shortages on Samsung's side, the world's leading AMOLED supplier, HTC has made the official switch from AMOLED to Super LCD to maintain productions of its handsets. Specifically, the HTC Desire and the Nexus One have made the jump from AMOLED to Super LCD.
The Super LCD panels are being made by Sony right now and according to HTC, offers comparable performance to AMOLED and has good battery efficiency.
You can expect new Nexus One and Desire units with new panels later this summer. Curiously, though, the Verizon Wireless HTC Droid Incredible, which have been plagued by the same AMOLED shortages, was not mentioned for the switch to Super LCD, also referred to as SLCD.