Documents revisions are a good TODO list container
While working on different documents and using many sources of information the user sometimes forgets what he was doing or even worste he loses his focus over the work without realizing this lost. I think that the best way to keep focused is do know what are you doing and in this way of thinking using Documents revisions is a very powerful way to do so.
Imagine GDocs to present you not the latest edited documents, but the concrete revisions of every document and this way to let the user to track his work.
In a relation with: Event Based Content Editor.
