In the forthecoming book I talk a lot about culture, i.e. tribes.
This is a neuromarketing thing.
We are wired for sociability and being sociable is very important for survival.

This also leads into the importance of segmentation studies in marketing.
Segmentation studies look especially for segments that relate to personality and culture issues.
Too many segmenation work in marketing is based on some pre-defined segmentation (like GenY or something) rather than looking for segmentations that relate to the market for the Brand.
I explain this more in the book.

Here is Seth Goldins talk at TED about 'tribes'. 
He might have called them cultures, or subcultures, or market segments.
From a marketing perspective what matters is identifying them - for new or existing brands.

From a media perspective what matters is reaching them cost-effectively.
The media fragmentation that has happened helps marketers to do this: the same media budget now needs to be split over more channels and each is better targeted than before.


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