I'm probably succumbing to "guy with a hammer" syndrome in a big way, but here goes...
From Jürgen Schmidhuber's "Compression Progress" talk:
[How] should an unsupervised intelligent agent... deal with data that is streaming in through the input centers in response to the actions that it's executing?
You have to find regularities in this history of inputs and actions that you store and... compress it.
So... what is the interestingness of some data X? Well, it's not the number of bits that you need to encode the data. It's the first derivative, the change of the number of bits as your subjective learning algorithm based on your subjective previous knowledge is improving the compressibility.
If I understand him correctly, Schmidhuber is saying that interestingness is your brain rewarding you for giving it new data that allows it to function more efficiently by encoding fewer bits. This he calls compression progress.
Why should this process be confined to visual and auditory patterns? Shouldn't it also apply to improvements in the compressibility of beneficial social data? Furthermore, shouldn't your brain have to constantly negotiate between rewards for novel, compressible social patterns and rewards for novel visual and auditory patterns? With social encoding occasionally -- or mostly -- winning?
Seen this way, culture looks like iterated niche-forming. Imagine a hunter-gatherer band with synchronized aesthetic values. Everybody follows the beat of the stone on the hollow log with nary an iconoclastic thought. Then the tribe gets bigger. Change in scale weakens synchronization. There is suddenly more variation in ideas. Subgroups form that may value intentional suppression of their former values, opening up social niches where the ability to notice small differences wins out over innate reactions. Basically, if difference-noticing can create a status niche, it will.
In other words -- and I'm only half-joking -- compression progress explains hipsters.