I'm struggling to see how NoSQL brings any advantages to a system, so I'm interested in hearing from people who have chosen to use it, both the reasons they chose NoSQL, and positive and negative experiences in implementation and use.
My first impressions are that NoSQL is a product of the availability of very large, very cheap storage; it seems that a million record database could easily have a 100MByte overhead in field labels embedded in the records. This goes against one of my software design instincts - remove redundancy in code and data whenever practical.
However, NoSQL is being used with success in large high-traffic systems, so I must be missing something, looking forward to your responses.