One of the traditional knocks on JS is the volatility of doing sql queries from a interpreted script. Not to mention security. In other words, how do you regulate resource for results in a varying client environment. Node.js is supposed to provide a server side capability. However I would be skeptical of it its implementation of a transnational capability. A memento pattern, or ability to rollback transactions, at least until thoroughly tested. Given the fact that most discussions are coupled with no-sql db's is a clue as to what its intended usage should be. Perhaps caches for local search tools like solr. Easy to update, and rebuild, but less likely to be an efficient engine for individualized rdbms queries.