I use rel-license since a pretty long time now and when I heard of hCard, I wanted to try it out immediately. But for several reasons I wasn't really sure, how to implement it. So now I just made a module and let it annoy me - therefore forcing myself to work on it some more! ;)
It's all about metadata, semantic markup and insert your favourite buzz-words. An image says more than a thousand words, so have a look:
In the bottom right corner, right besides the 20 Errors (yes, I'm not yet ))W3C-compliant(( :P ) you see the microformats-logo. After double-clicking it, the Tails FireFox extension opens up in the left column and shows my vCard. The tails-extension is far from perfect, but it is a very good tool for recognizing microformats on pages and getting an initial look at them. There are other extensions, that directly allow to add contacts to your address-book, etc.