Times Square is no longer an unusual attraction; it?s the norm. The side of a building can now be made to broadcast video. There is hardly a public space left ? a bar, a gym, the dentist?s office ? that hasn?t been vanquished by some kind of screen. Now, let?s say I?ve got something to sell. This multiplicity of screens would seem to be a good thing, wouldn?t it?

What the proliferation of screens has done is give a bazillion creators the power to publish. There are now billions of hours of content, which means new places for advertisers to latch on to ? lots of content that pockets of people find interesting. But the shift you?re describing makes things more complicated for advertisers too.

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