This feature allows users to be able to quickly and correctly attribute a work, including extra metadata that is useful for machines.
For example, when you click on a license badge that includes RDFa about the work, you are presented with the dynamic CC license deed that gives the viewer a chunk of code to use for attribution.
See the screenshot below for the code chunk:
The code that is provided in that text box is:
<a rel="cc:attributionURL" property="cc:attributionName" href="http://grossmeier.net">Greg Grossmeier</a> / <a rel="license" href="http://creativecommons.org/licenses/by-sa/3.0/">CC BY-SA 3.0</a>
This produces text that looks to the viewer as simply "Greg Grossmeier / CC BY-SA 3.0" where the name is linked to the original work (http://grossmeier.net) and the license name is linked to the actual license (http://creativecommons.org/licenses/by-sa/3.0/). The added metadata also tells machines what those links mean and who the author is.
The exact format of the text can be changed, the only real important part is that the information is there and surrounded by RDFa.