After all, Chromebook users are supposed to store their files online and there are many services that offer more free storage than Google Docs: from Dropbox (2GB) and Box.net (5GB) to Amazon Cloud Drive (5GB) and Microsoft SkyDrive (25GB). While you can buy 20GB of storage for $5/year, it's obvious that more people would upload their files to Google Docs if the service offered at least 20GB of storage for free. Releasing a sync software like Music Manager would make it easier to upload files and to access them from any computer.
Another idea would be to separate online storage from Google Docs apps, so that you can upload Microsoft Word documents and open them using Google's word processing app, but without irreversibly associating them with the app. This way, you could upload files and open them using multiple applications, for example: Google Docs, Zoho Writer and Microsoft Word's Web App.
Image by Scott (inspired by Hyperbole and a Half).