When advertising meets surveillance

From the New Scientist:

With electronic billboards, processing power cameras and other sensors becoming ever cheaper, it’s become possible to manufacture products that allow web-like targeting in the real world.

For example, a system developed by Singapore’s research agency lets advertising screens detect the genders of passers-by: it will soon be able to tell how old they are, too. IBM has worked on systems that can scan a crowd and estimate numbers, demographics, and where people are looking.