I played and cut with it some last night, just a little bit. There are some HUGE advantages to using the CDS software over just your Cricut. First, you can see exactly what you are cutting and where, so there's no guesswork as to paper placement on your cutting mat. That is wonderful! You can really make the best use of your paper by arranging things where you want them and making sure that they line up just right on your paper. You can stick down several different papers in different places on the mat and design accordingly so you can make all your cuts at once from a few different papers. You can also weld letters together to make words, which is great! That's a feature I plan on using a lot. Actually, I plan to do all my designing and cutting from the computer now, since it is so much easier than using the touchpad and screen on the Cricut!
Unfortunately, just in my first hour of playing with the CDS software, it's obvious that there are some areas that could use some serious improvement. It would be great if there was a way to erase lines you didn't want cut, or to fill in frames that you've made so they are just solid blocks. Right now I can't figure out a way to do either. There are also a few things they could do to make maneuvering the cuts on the mat a little easier. But all told, it's pretty good.
So far I'm enjoying playing with it. I made my first real "project" with the Cricut and Design Studio today, so hopefully I can get pictures of it up soon. It's pretty simple, but I did it all in one cut, and I'm pleased with how it turned out. And that's always good, right?