Is something I see content or an ad?
The lines between content and advertising are so blurred that it is much like physics where light behaves as both a particle and a wave. Okay, the concepts of particle and wave don't apply with really small things like those found in quantum physics but when viewed from those terms things behave strangely.
It seems that marketing is moving toward a duality where something we see is both content and advertising. At the scale of TV or even print magazines, it is relatively easy to separate the two concepts. One is used to financially support the other - everybody knows how the game is played.
But what happens when the unit of consumption is very small -- a search result, a blog entry, a posted video, a mobile message? At what point do 'content' and 'advertising' lose their meaning?
The rush to monetize ever-smaller pieces of content may reach a limit where uncertainty creeps into the equation and we're left in search of a completely new explanation and business model. If there are no direct costs of producing content, why do we need advertising?
For a variation of this topic see Steve Smith's post on the impact of mobile messaging on branding.