Logstash 2.2.0 and 2.1.2 is available for download today as part of the release bonanza! 2.2.0 release includes changes to the internal architecture of the pipeline, but is still backward compatible with old configuration. Read below for highlights, and check the changelog for more details.
Logstash 2.1.2 is mainly a bug fix release, and its changelog can be found here.
Blog: https://www.elastic.co/blog/logstash-2-2-0-and-2-1-2-released?blade=tw