Another example of marketing applications for AR...but is it usable.

QR codes will be popping up everywhere soon. Facebook will be launching
them and accidentally (or purposefully) they were briefly seen on
Facebook accounts earlier this year.

http://mashable.com/2010/11/11/online-offline-marketing/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+Mashable+%28Mashable%29

I'm interested in them as a more convenient way to interact with objects
and information. Object recognition seems a way off practical use.
However QR codes or AR markers provide a stepping stone.

I fear that standardisation may be a problem. I don't know if there's an
industry standard. The Wiki page seems to indicate there isn't.
http://en.wikipedia.org/wiki/QR_Code#Standards

It just won't catch on if users have to have the right software. I must
be mistaken. There simply must be an industry standard. Otherwise we're
back to pre-TCP/IP days where each network had it's own protocol and
none of them synced.

I must be wrong.