Diving in after release. Veteran/Ironman.
I've only played an hour and haven't noticed significant changes. As Scott said, the music is more varied and pretty good. And the map seems to have more points of interest. Maybe it is the luck of the draw, but previous maps had less villages/towns/keeps, etc.
Veteran level is tough.
Seven brothers, marching under the banner of the Weeping Queen, in search of seven brides barely survived their first one skull mission. They faced five nachzehrer in a graveyard.
One brother was clawed to death. Wolfram the Pessimist now has a gaping hole where his nose once was, a permanent injury that reduces his fatigue by 10%
And Kori the Bull took a blow to the head that "shook some things up and didn't exactly benefit this character's cognitive skills (a permanent -25% Experience Gain and -25% Initiative). On the bright side, he may now be just too stupid to realize when it's time to run." (+15% Resolve).