Hardware-wise, this concept is not too compelling. Needs physical buttons. Needs the trackball. I don't want to pay for stereo sound or the ability to turn into an alarm clock. Give me battery life and a higher-res screen instead. I don't want gimmicks, I want a solid phone that always works and doesn't get in my way.
I agree that they should make their "premium" phones out of metal, though. I think Apple is leading the way here (with a metal case and a very high-res screen), and that HTC is just going to copy. But that's fine, an Android-based iPhone 4 clone with WiMax will be phenomenal.