Seth Godin, bestselling author and Agent Of Change, writes prolifically about viral marketing and IdeaViruses in his famed book. It's live example is his venture Squidoo.com, an online service collecting innumerable hand-built user-pages, each a focused, useful guide (Lenses) on an area of expertise...i.e. a one-place quickest way of "getting things done"...say 'How To Find A Job In A Day', 'How To Choose A Perfect Diet For Your Pet' and just like that!
The novel marketing model (read: Permission Marketing), more prevalent in Internet advertising for now, is based on word-of-mouth contagion model, owing to the fact that Ideas can be much more contracting than anything else. Seth avers that we live in winner-takes-almost-all world, and now masses are more connected than ever and profit margin for creating and owing an ideavirus is huge.

...And little Jane asked: "Mom, will my world all be a clutter and muddle forever..."
Comments
Yeah rightly so, Internet is as much an advertising playground than a knowledge/re-creational workplace...
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