NoSQL is a Premature Optimization « SmoothSpan Blog: "Point 2: There is no particular advantage to NoSQL until you reach scales that require it. In fact it is the opposite, given Point 1.
It’s harder to use. You wind up having to do more in your application layer to make up for what Relational does that NoSQL can’t that you may rely on. Take consistency, for example. As Anand says in his video, “Non-relational systems are not consistent. Some, like Cassandra, will heal the data. Some will not. If yours doesn’t, you will spend a lot of time writing consistency checkers to deal with it.” This is just one of many issues involved with being productive with NoSQL."
