I'd really like to see a set of use cases for each type of system too. I recently compared NoSQL systems in terms of the CAP theorem and the underlying data model (discussion here http://news.ycombinator.com/item?id=1190772). I haven't seen enough of these systems in production, but it would be great to see examples of each combination of CA, AP, or CP systems with relational, key-value, column-oriented, document-oriented, and graph (not featured in my post) data models.