[jlees]

You need to find a set of people who are connected and connectors, and who have this kind of problem in spades. Then build in sufficient virality so they all start using it, and as you point out, multi-platform presence. Many folks have tried to replace the business card and failed, but I've seen cards with custom URLs rather than contact details on them; maybe that's one way to go. (QR codes require too much friction.)