RDFa in flickr?

I remember hearing that flickr was using some RDFa, but I can't find any 
mention of it anywhere. After doing a View Source on a few flickr pages, 
I found a single property="dc:title" attribute in each photo's page 
(e.g. in http://www.flickr.com/photos/bobdc/2119795376/)--just enough to 
tease me.

Does anyone know anything about this, or did I just dream it?

thanks,

Bob