Google adds collaboration support to Microsoft Office
googledocs.blogspot.com
googledocs.blogspot.com
For those who don't know them, Google acquired them last year presumably to build exactly this.
From my experience, integrating with MS Office/Outlook APIs is no walk in the park, so syncing with Docs is friggin' amazing.
Oh how I miss etherpad.
In case all you want is to access your documents as files: http://code.google.com/p/google-docs-fs/
I suspect MS thought they could do this in the enterprise via SharePoint first. I think now they'll have to change their plans.
Just like Google ChromeFrame and IE9, I hope this pushes the Office folks to release something better so the Google "barnacles" don't destroy their platform.
"Microsoft Office 2010 enables technology known as co-authoring, which gives you the ability to edit the same file at the same time as people in other locations. No more waiting in line to get your work done, no more getting locked out of your files, and more options for real-time collaboration with your team. What applications enable co-authoring? You can use co-authoring in the Office 2010 versions of Word and PowerPoint. Co-authoring via shared notebooks is also available in Microsoft OneNote 2010. And, simultaneous editing is also available in Microsoft Excel Web App and OneNote Web App."
Although it looks like there are kinda weird limitations on it, in that apparently Word and PowerPoint co-authoring only work in the desktop apps (and not in the web apps, but you have to save to SkyDrive), Excel co-authoring only works in the web app (and not in the desktop app), and OneNote is the only one that works in both the web app and desktop app.
If Google isn't using undocumented APIs, then they're doing exactly what Microsoft wants: developing software that "plugs in to" the Microsoft ecosystem.
"Oh hey, this Google Docs thing works pretty well in the browser. Why do we have a separate program again?"
Edit: as another commenter mentioned, it also has co-authoring; not as slick at google docs at chatting, but it worked well for me.