I've been a fan of QR codes\u2014or "quick response" codes\u2014since learning of them in a story I wrote last year about how a Texas town implemented them as part of a modernization project. QR codes have been huge in Europe and Asia for years, but the technology hasn't gained traction in the U.S. Until, perhaps, now.QR codes are two-dimensional bar codes that are read by an application for cell phones equipped with a camera. You scan the code with your cell's camera and the browser brings you to a site with more information on the designated item. For example, that Texas town placed QR codes on landmarks; scanning the codes brought visitors to a website that described in more detail what they were looking at. Now, it appears that Facebook may be rolling out QR codes to profiles\u2014there are reports that some users have already received the two features\u2014"View QR Barcode" and "Generate status QR barcode"\u2014but as of yet, they don't seem to be functioning.If Facebook does decide to roll out the feature, it would undoubtedly send the QR code technology mainstream\u2014and could change the way we use Facebook. Consider these two scenarios: You meet someone at a conference and instantly connect with them via a QR code printed on their business card. Or you pass an advertisement for a product and instantly access its Facebook fan page to learn more. Using QR codes\u00a0will be\u00a0another way to blur the lines between digital and physical relationships. Do you think this is a good idea? Would you add a QR code to your business card?Do you tweet? Follow me: @kmburnham.