The Ability for Google Admins to Restore a User's Deleted Files
If a user accidentally deletes an important file and empties the trash, there will soon be a way to restore it!
The Ability to Edit Microsoft Office Files directly from Google Drive
Users do not even need to have Microsoft Office. On Chromebooks, there is nothing to install, it will just work. Google Apps users on PCs will need to install the "Office Editing for Docs, Sheets & Slides" extension, and it's free.
The Ability to "Suggest Edits" in a Google Document
Users with "can comment" access to a document can suggest edits, which will appear right in the document along with a comment explaining the edit. I think teachers will like this as they provide feedback on student work.
The above changes will be released first to "rapid track" domains, and then slowly to the rest of us. It's great that updates like this happen automatically without needing to install new software. Thanks, Google!