MongoDB Now With Sharding and Replica Sets
MongoDB 1.6 is out now.
New in this release, is sharding, which makes MongoDB 1.6 horizontally scalable and gives developers the option of upgrading a single instance of monogod to a distributed cluster with zero downtime. Replica Sets are also now available. Please note that replica pairs are now deprecated. Outside of sharding and replica sets, concurrency has been improved and support for IPv6 and UNIX domain sockets has been introduced.