You're right--I definitely simplified the discussion of handling concurrent writes. Keeping around concurrent versions and using user-specified merge functions

You're right--I definitely simplified the discussion of handling concurrent writes. Keeping around concurrent versions and using user-specified merge functions are two ways of deciding which versions to store. Riak indeed supports keeping concurrent versions or using an automatic last-writer-wins policy [1] The question of which versions will be returned depends on the safety properties of the consistency model. My main point isn't that Dynamo or Riak don't provide safety properties, it's that "eventual consistency" isn't a safety property on its own. [1] http://wiki.basho.com/Vector-Clocks.html http://wiki.basho.com/Vector-Clocks.html