At FTF (Freescale Technology Forum) in 2011 at least (didn't go this year), used them on everyone's name tags and booths, so rather than passing out business cards, you used the iPod to scan them and it would send you a nicely formatted email along with the contacts for easy importing into whatever contacts you used. It was about the only time I felt they were done right.
And if you scanned the codes that were given in the different tracts, you were also sent the PDFs and slides of that tract.
Oh yea. If you paste an image into OneNote, it'll auto-OCR things and index them.
If you record audio into OneNote, it'll index the audio, synchronized to any other notes. I've used this on multi-hour meetings, to jump right to places where I think one party said something. Amazing.
COULD do that, or you could have all the information that they already submitted (it was more than just a vCard). I would rather not have to proof read all the OCR (there are hundreds of people at FTF)
The Heartland Developers Conference did the same thing this year. The QR code included more info than just the text on the badge so OCR would not have gotten the email address.
And if you scanned the codes that were given in the different tracts, you were also sent the PDFs and slides of that tract.