The Tipping Point presents the theory that in society a small cause can have a small effect a small effect and then a large effect. For example, crime tends to rise and fall sharply (perhaps in the span of a year) after remaining constant for several years. In other words trends apply to many more aspects of the world than we intuitively feel that they do. Since this is the German edition, it is worth knowing that most of the examples Gladwell gives are from the US. I don't think that this is a problem at all, but you might want to know.
Gladwell addresses word of mouth advertising to spread ideas and trys to identify just what "tips" an idea - what makes that idea spread and get really big. He identifys three types of people who are very influential in determining what ideas become prevalent in society: connectors, mavens and salespeople. According to Gladwell, Connectors are the sorts of people who know everyone. They don't know them well, but they know them and can get in touch with them again if they have to. So they can pass messages between strangers who would benefit from knowing one another and spread a new idea to a large number of people.
But I delete most mass emails (you know, the five forwards a week from the connectors in my life), so just knowing people and spouting information at them is not so effective. Hence Gladwell's idea of Mavens. Mavens are people who are really into something. Whatever they are into that's what they are a maven of. When they are exposed to something related to what they are into they will research it and friends who know they are into it will tend to ask their advice. So their opinion of something new matters very much because others will look to them for judgement. A good example is an investment strategy. A maven for this is into different types of investments and friends would naturally tend to ask their advice, so for a new plan to become popular is much more likely if it appeals to these people.
And Salesmen are people with contagious personalities who can change other people's minds. If someone with this personality type happens to like an idea and talk about it then that will contribute to the idea's popularity.
So we are presented with the idea of three influential personality types who determine through intricate coincidences what the general public knows. For each of these examples Gladwell goes into digressions in which he give historical examples of the personality type and finds and interview one example of each from today.
Obviously what the idea is has something to do with whether or not it spreads. According to Gladwell, inherent in the idea are Law of the Few, the Stickiness Factor and the Power of Context. (here the book begins to apply to marketing strategies) The Law of the Few is basically that some people are much more likely to take risks and try new things. If they pick up on something then at least its out there. Most of the examples Gladwell give for this relate to fashion trends, although adoption of hybrid corn is an example of something less arbitrary in which statistics show that a few farmers adopted it then a few more and then everybody else. The masses watch how things are working out for the experimental few and then if things are good the masses follow.
The Stickiness Factor relates directly to advertising. How many commercials have you seen which you remember clearly and yet the product being advertised is forgotten? To demonstrate the Stickiness Factor Gladwell gives many examples from children's television. For children repetition and centering on the screen the idea being taught (for example letters with the muppet behind them on Sesame Street) are very effective for the children to remember what they saw. Here he deals with psychological studies and what determines what sticks in people's heads.
Gladwell's discussion on the Power of Context describes how environment affects people much more than one would intuitively believe. He gives examples of waves of suicide in which a publicized suicide subconciously gives "permission" to others. He also describes the sharp drop in crime in New York in the 90's. In this case the police focused heavily on small crimes. For example, they removed all graffitti and kept graffitti off the subway. Gladwell also cites psychology studies which point to environment being very important in determining behavior.
The Tipping Point was an interesting and entertaining read. If you read it, read it because you are curious. It doesn't give practical advice on marketing, rather it just provides theories on how the world works and give evidence for those theories.