I whipped together a php script this afternoon that allows you to make arbitrary queries for Gerrit change sets, and then perform bulk actions on the resulting change sets from the command line. Currently it only supports doing a bulk 'submit' (with approve +2 and verify +1), but it won't take much to add in other things (like abandon, verify, approve, etc). Take a look and feel free to comment/make changes:
http://svn.wikimedia.org/viewvc/mediawiki/trunk/tools/gerrit-dippybird/dippy...