Rob, that is about the best description for my experience with SketchUp. I have used quite a few CADD programs over the years and found SU non-intuitive at first. Once you get used to the idea of pushing and pulling instead of cutting, it's pretty easy. The trick is to not think of how you would mill wood into the desired shape. Get used to creating holes by pushing circles and squares through an object instead.
I was debating on picking up a professional CAD package that I already know (either AutoCAD or MicroStation) before I stumbled across SU. This tool has saved me a bundle since I've completely redesigned projects before they have even hit to prototype stage just by modeling them in SU. I do find the lack of good materials a bit bothersome though. Has anyone found a good materials library for woodworking?