People are interested in this phone alot for several reasons:
-HTC phones are more friendly to rooting/hacking and 3rd party roms.
-They have sense, which is arguably the simplest, and least intrusive manufacturer OS overlay of the bunch(with samsung and moto prob being moreso intrusive, and most likely the easiest to remove, if you want the nexus one style stock google experience.
-It has the 4.3" screen off the EVO, and this is good because it is wider than the DX and thusly easier to type on in both portrait and landscape. The DX is more freindly to avid you tubers and movie watchers as its screen is taller, thinner, and in the 16:9 ratio which is universal for widescreen movies etc,.
-More ram
-2.2 stock
-Kickstand!
-front facing camera(we hope)
Now obviosly this is all based on pics and meager info we have so far. But for somebody like myself who has been waiting for the verizon evo, this is the perfect excuse to kick my iphone to the curb!