We get this a lot actually (understandably) This video is a great example of nosql approaches and in fact there is a load of issues highlighted that when you looks at MaidSafe you will much more easily understand what and why we have done this and why it’s so complex.
I hope this helps a bit, but imagine a key/value store with security and with the issues of integrity and atomicity solved.
Think Amazon Dynamo, its very very similar in some ways although not as scalable or secure as the vault network. The routing layer allows high speed accurate xsfers of data and proximity information. So maybe Cassandra like scalability or even haddop with distributed name servers and multi function nodes distributed globally (so not in single data centres).