Wow; old thread.
CC3's interface is essentially the same as CC2's, but they've added quite a few features. It can be a bit counterintuitive to learn, especially if you've previously been exposed to a paint program like Photoshop or Gimp. CAD users, on the other hand, will pick it up fairly quickly, since it is built on a CAD engine. It's definitely more difficult to learn than Photoshop, but a great deal easier than something like Blender.
And since this is such an old thread, I should amend my earlier post: ProFantasy has added antialiasing to CC3. I haven't used it since that was added, but the maps produced by other CC3 users have been looking significantly better recently now that the "jaggies" are gone.