Savanna is an OpenStack component that allows elastic provisioning of Hadoop clusters in OpenStack. It has a 3 phase roadmap - phase 1 allows basic cluster provisioning which is complete, phase 2 will add advanced configuration and tool integration currently in progress, and phase 3 will enable analytics as a service with a job execution framework. Savanna uses an extensible plugin architecture to provision Hadoop VMs and configure the clusters, integrating with other OpenStack components like Nova, Glance, and Swift.