New HTC Sense
New Snapdragon, which is more power efficient, has more potential for overclocking, and is just all around better than the old one.
SLCD screen rather than the EVO's LCD screen (those who complain it's not Super AMOLED: remember what happened with the Dinc...).
More RAM
Probably more phone memory and internal storage
32 gb microSD card included (whoa, eat that iphone, this'll probably be cheaper than the 32 gb version, too).
It's a pretty decent step up. Not a huge one, but yeah...
Dual core is nice, but we don't know when an Android version that supports it fully will come out (rumored to be Honeycomb).