BETA 4 update
Horizons 2.0
Shamelessly ripped form my twitter feed, I present to you the latest in ground variation and terrain mapping that FDev has provided to date:

Thanks to @fireytoad for the image (a good streamer and supporter of ED).
Not pictured is the addition of subsurface scattering for ice. This makes Europa, and mixed rock/ice bodies far more interesting to land on, with areas of opaque, gritty ice/rock mix surrounded by translucent glacier-like canyons.
FDev are going all out on spectacle and accuracy, and this is something we'll see continue when they begin to model atmospherics later next year.