So you want to go with the flow and implement your next application on top of some NoSQL, NotJustSQL, NewSQL, AlmostSQL, SQL++, NextGenSQL, and what not, just to be sure not to miss out on some of the latest developments in the data business? Here’s a little map to guide you through the jungle of choices:
http://gigaom.com/cloud/confused-by-the-glut-of-new-databases-heres-a-map-for-you/
… or you just stick with the relational data model and some decent RDBMS like Oracle, SQL Server, or Postgres and wait until things settle a little bit :-)