Our top learnings from two years of Google Docs?
1. Google Docs relieves a lot of the pain from sharing attachments. It's worth using.
2. Colleagues working on the same GDoc during a meeting cuts a lot of review cycles short. It's a great relief.
3. Native Google Docs do not consume space from your storage quota, while any other format does. So if you have legacy documents it is wise to take the time to convert or at least decide how important they are.
4. Naming conventions for GDocs require re-education of old habits.
5. Document lists and searches of Google Docs are incomplete and hence buggy, which creates frustrations.
6. A Google Sites intranet page by topic, with index pointers to relevant Google documents, makes it easier for everyone to find what they're looking for. Such index pages centralise the maintenance of document lists and work around Google Groups bugs.