Open Source Database Explosion

I am spending some time researching various open source and cloud computing service providers using the exhibitors list for OSCON 2010. Audrey needs some tech research done, before she attends the event. She wants to be prepared So I'm going through each exhibitor and learning and documenting as much as I can.

One thing I'm seeing is an explosion of open source database offerings, I'm counting seven systems (yes I didn't include Oracle): I'm seeing a big shift away from the database world I've known for the last 15 years. Microsoft SQL Server, Access, Oracle, and MySQL. I'm seeing a big shift with cloud database providers like Amazon SimpleDB and Google Fusion Tables. And I"m seeing an all out mutiny with the NoSQL movement. Seeing all this energy and change with databases after 20 years in the business is really exciting.