Does the HTC Desire support 'microSDHC'?
the "HC" in every SD-Card name simply means "high capacity" - i.E. every SD card with more than 8GB is a SDHC card. Every "SDHC" Card is SD-Standart 2.0 ("SD 2.0"). Which means your device is compatible with a microSDHC card up to 32 GB.