Alright, so I run logstash 1.2.2 like so:
$ java -jar ~/software/solrlogmanager/logstash_deploy/logstash-1.2.2-flatjar.jar agent -f logstash.conf
And it outputs this:
Using milestone 2 input plugin 'file'. This plugin should be stable, but if you see strange behavior, please let us know! For more information on plugin milestones, see http://logstash.net/docs/1.2.2/plugin-milestones {:level=>:warn}