They're really pretty different. The DInc 4G is very much a progression of the Incredible line, keeping closer to the form factor of the previous Incredibles. It has a slightly smaller screen and the plateau back cover.
As far as specs go its not quite as clear as it seems. A quick glance seems to give the Rezound the edge but dig a little deeper and you see that the DInc 4G has an S4 processor, a huge step above the S3 in the Rezound, despite the lower clock speed. The screen is lower res on the DInc 4G but it is a smaller screen so image quality should be very comparable. The cameras are almost identical with the addition of BSI (backlit sensor) on the DInc 4G which will offer a slight improvement over the already very nice camera on the Rezound. Add in ICS and Sense 4.0 out of the box (Rezound will get ICS but only with Sense 3.5 or 3.6), NFC, the better efficiency of the S4 (meaning better battery life) and the DInc 4G starts to come to the top a bit. Its really going to come down to personal preference between these two.
I'm definitely going with the DInc 4G as I have been waiting on a 4G HTC phone with a 4" screen.