Personally, I am a huge fan of the Google Apps, both for personal and professional life. In the school setting, it is a great way for students or teachers to collaborate and provide feedback. Google Apps also save all prior drafts, so they can be examined for changes over time. I like how everything is saved to a central area and access can be controlled by the creator. The ability to determine who can see and edit is perfect for posting documents to students. I also like how the Google Apps are available to anyone who has an internet connection and doesn't require them to purchase special software.
At our school, we are working on convincing the administration to convert to Google Apps for email and more. Our administration is reluctant because of legalities regarding storing emails for extended lengths of time and data safety with students. However, we have seen many good electronic data walls using Google Spreadsheets and would like to be able to have all of the data accessible to staff at all times and easily sortable.