Although fun, it is quite shallow. It needs more depth to win my vote.
The next best example of mobile advertising from Carling would be if you could add some sort of value in beyond a neat trick, like actually having your pint waiting for you at the bar or brought to you if you order on your iPhone so you can avoid a ten-deep human barrier between you and your cool, refreshing beverage. Probably would get more Carling sold too, which would "stretch the definition of what advertising is" even further.
[It's the accelerometer in the iPhone that Carling has exploited. The accelerometer is the interesting bit. And for no reason other than it's possible it would be cool to know the tilt of every iPhone user on the planet. Making the half-decent assumption that facing up and moving a bit equals movement and down flat equals inactivity it would provide an interest peek into people's activity.]