I just finished one adorable episode where the kids traveled to visit reindeer and learn what they eat and how the find it. Next they befriended a spider and learned how a web is made. I didn't know some of the web-making details (I'm a 52-year-old scientist) but it was presented in a fun and entertaining way that anyone could understand. My daughter is 3 years old and I'm sure she doesn't get all of it, but she loves to watch and it certainly isn't too simple for her. It is for children, but Martin Short is doing the Cat-In-The-Hat voice and he is a huge talent and always funny. I think it is very amusing both for children and adults.
I'm watching it in high def on a 1080p HDTV and it looks fantastic. I have no idea what the other reviewer is talking about. The animation is pleasant to watch and I don't see any problems with shading -- I don't think there is any shading.
Anyway, it's a great new show. It is educational and fun. We'll definitely be watching it for a few years.