I suppose you still have to have a way to give people your LinkedIn URL, but this is definitely a step in the right direction. Save the trees!
Scott Allen is a social media pioneer, helping people turn virtual relationships into real business since 2002. He is coauthor of The Virtual Handshake and The Emergence of The Relationship Economy and contributor to over a dozen books on social media, business and personal development.
One way to save everything for no printed business cards. Cool idea through LinkedIn URL.