Google Docs has added the only feature I thought that it lacked, support for Word, Excel and PowerPoint 2007. I never upgraded from 2003 simply because Microsoft Word 2003 is the most perfect software application ever built. I never wanted to take the time to download the addons to open .docx or .pptx files either. That is no longer an issue because now, directly from gmail I can open up the docx files and let Google take care of business.
Google Docs now supports .DOCX!