How "Location Shifting" Could Reinvent GeoTargeted Online Marketing

There's a pretty simple idea that could transform the landscape of targeted online communications, but no one is doing it ... yet.  If you have ever done any online marketing that has been targeted by geography, you know that there are pretty much only two ways to do it currently online:

1. Based on IP address of where the user is accessing the Internet. Notoriously unreliable because of shared servers and inability to truly pinpoint a user's location.
2. Based on a profile that the user has created indicating where they live. This is much better with two big assumptions ... that people tell you the truth about where they are, and that they are usually there (as opposed to travelling).

For someone like me, this system makes it impossible to target me on a geographic basis. I am always travelling, often using Internet through shared connections in multiple locations, and my Facebook profile says I belong to the San Francisco network (intentionally), even though I live in DC.  My email address has the word Australia in it and I registered it while I was living in Australia and never changed my region. There are a lot of other consumers like me, making it tough for any business to truly target geographically by relying on such uncertain data. The one solution with promise involves using the mobile platform to geotarget based on where a person physically is. This is good, but still incomplete because it doesn't allow you to predict where someone will be.  What if there was a way to geotarget your messages not to where a user currently is, or even where they say they live, but to where they will be?

This is possible today, because more than ever before, people are now broadcasting where they are going to be and what they are currently doing through social media.  Look at a platform such as Twitter, where people routinely update their status to indicate where they are and what they are feeling.  Or a travel site like Dopplr, which I use to update my upcoming trips.  To a degree, this is private information - but many people publish it live for anyone to see.  Location shifting means geotargeting your marketing communications based on information about location that your consumers are giving you or posting online.  As a result, if smart marketers started using this information, a whole range of things could be possible:

1. Banks could verify that you are travelling and not have to cancel your cards because of suspected fraud
2. Marketers could send special offers to people who express a particular sentiment in a certain location (eg - someone Twitters that they are hungry in Manhattan, and gets a Twitter message back with a coupon to a local pizza shop)
3. Car services could automatically update their drivers who are waiting for pickups
4. Your friends could invite you to events through social networks based on where you will be and not just where you live

What else could be possible with location shifting?  Let me know if you think this idea works.