Matt Cutts writes:
In some circumstances, Google uses descriptions from the Open Directory Project as the title and snippet for a web result; this tag lets you opt out of the ODP title and description.
This can be pretty annoying if you want your chosen title to appear in the Searchengines and someone else submitted your site into dmoz with a totally or slightly different title.
<meta name="robots" content="noodp" />
So that’s indeed a very cool meta tag and you should use it by default, just to be safe.