Probably the biggest benefit to me about the availability of a service like Google Docs is that you can almost eliminate the need for Microsoft Office. Not only is it a hassle with different types of documents (.doc / .docx) being forwarded through email, but it is expensive to have on your home computer or laptop.
In addition to eliminating the need for Microsoft Office, Google Doc is easy to use. Has all the same options as Microsoft Word and it is very user friendly.
I guess the only downside to this is you have to have Internet access. For most professionals in the educational field that wouldn't be a problem, but for high school students it may.