According to HTC source, it look as if the HTC Desire will be coming to the US in August. As far as what carrier, that is unknown.
The phone itself will be sporting HTC Sense v2.1 (Eclair), 576 MB RAM, 512 MB ROM, and Qualcomm Snapdragon QSD8250 1 GHz processor. This may be old news for some, but great news for many.