0.11.0 has just been released. You can download it here. This is a major release for elasticsearch, both in terms of feature set as well as stability.
Major list of features include:
Zero Conf Persistency
Out of the box long term persistency using a “local” gateway dubbed zero conf persistency.
A new API to do bulk indexing of data, greatly increasing the throughput of the indexing process. Details here.
Thrift REST Transport
A Thrift based REST transport (mimicking HTTP) for faster execution compared with plain HTTP.