I recently finished developing a course using the new iTunesU course creator. It was an interesting experience which I've reflected on over on my blog.
The course that I created is a professional development course titled "Google in the Classroom." The course is designed to help teachers learn how to use various Google products (Docs, Sites, Calendar, etc) in their classroom. I included lots of project ideas from educators around the country to get people started. You can view/access the course here.
The best part about the new iTunesU is the ability to organize course material in a logical sequence is. My only complaint is the lack of 2-way communication between the instructor and the students. I'd love to see a discussion board feature added to allow instructors to receive feedback and questions from students. That would make the iTunesU app a powerful learning tool.
If anyone else has/is using the iTunesU course creator, I'd be interested in hearing about your experience. This is a pretty new tool that hasn't gotten a lot of use yet, so I'm interested in hearing the thoughts/experience of others.