Finally...

<< Over the next few weeks, we’re releasing three additional features to make it easy to upload files to Docs: folder upload, documents list integration, and drag-and-drop upload.

To start, we’ve added folder upload via the new Upload menu in the latest versions of Chrome, Firefox and Safari. >>

http://googledocs.blogspot.com/2011/04/simpler-file-upload-in-google-docs.html