Part of the reason though is it is easier to get an idea of what you need from a NoSQL database and what you'd be giving up if you are already on an RDBMS, righ

Part of the reason though is it is easier to get an idea of what you need from a NoSQL database and what you'd be giving up if you are already on an RDBMS, right? I think the advice is right on and I see NoSQL databases as very much useful adjuncts to the relational systems, not as replacements.