Google's minimal progress towards sharing files - now PDF

So now we have Google's own products and a PDF viewer:

Google Docs supports PDF upload, viewing and sharing:

...Google Docs now allows you to upload PDF files to store them online. You can view uploaded PDFs right in your browser, and determine who else should have access...

Sharing PDFs through this mechanism is very helpful, I'll definitely make use of this.

The news does, however, remind me that it's been two years since I expected an imminent general file serving function for Google Apps.

Clearly, there's a reason they don't want to support other file types. Copyright violation? Performance? What?