I like the ability to communicate with others and work through discussion boards. Communication is always a good thing with out work, but it can sometimes get overly complicated. Especially when we work with people who are less familiar with modern technology, it ended up being a crutch more than a useful tool for our purposes.
I dislike that so much had been relegated to the program. Though it is good for assignments and projects to be listed, many users do not post them. Unfortunately as well, when information is so readily accessible to everyone, it become more and more difficult to "shut off" work. With less efficient professors, students had to frequently check their assignments to see if they were posted. If not correctly set up, quizzes can also be overly objective in their responses. This is more operator error, though.
It seems to be the best option for us, but keep in mind that online learning and collaborating is often more difficult than face-to-face learning styles. The program itself is great, but administrators need to ensure teachers are using it well.
It is good to be able to post projects and work on them together. When we had assignments that were due, it was nice to be able to collaborate together, think about possible solutions, and even post or work with the moodle program. However, some would have issues uploading. Ultimately, graders ended up printing everything out anyways.