I've tried Google Docs before in order to share spreadsheets, and I love the way it works. It really does make it so much easier when everyone can access and edit the data in one place, rather than everyone working on their own PC and then trying to compile the data! I don't see the same benefit in documents, but I'm sure it would also have its uses there.
One interesting thing might be that the use of these web-based apps would actually encourage people to collaborate when they might not have thought of doing that otherwise. If so, that would be an interesting change with all kinds of implications!
Since the first time I used Google Docs, I've thought of even more ways to use it, again, mostly the spreadsheets - we're capturing vendor information there now. However, with Microsoft SharePoint coming soon, I would expect most of my shared documents will move there - feels a bit safer to me.