Moodle does a very good job of monitoring students, giving assessments/grades, providing content, and doing discussion forums. It does not do a very good job of synchronous collaboration, wikis, email, or any of the other things that Google Apps does an amazing job at. I guess that is why Moodlerooms decided that it would be a great idea to get the two projects together and create an easy way to do single-sign-on.
I am amazed at the potential for something like this. Imagine being able to log into your classes, your e-mail, your sites, and your docs all at one place. Well, after much working on my own installation, I would like to provide a simple how to for making this process happen in your Moodle instance: