Photo from the Austin Java Users Group, March 25, 2014

Tyler Hobbes spoke to 85 Java developers about Cassandra, the NoSql database created at Facebook, but used by Netflix, reddit, ebay and instagram. My bullet points:
Cassandra has no Master-Slave architecture, but instead has a network of peers all sharing data.
Cassandra is fully distributed and has no Single Point of Failure (SPOF).
They use Murmur to build 64-bit hashes.
Yuki Morishita talked about Cassandra Query Language CQL.
You can use sqlsh, a command-line version of CQL.
Cassandra is not good for ad-hoc queries, the database structure has to be designed for your planned queries to be useful.