It’s not surprising that the new book Contagious: Why Things Catch On, by Jonah Berger, is itself catching on and getting lots of attention. Berger, who is in his early 30s, is the James G. Campbell Assistant Professor of Marketing at the Wharton School at the University of Pennsylvania. He studies and teaches about how and why products and ideas go viral and get other forms of attention, both online and offline. These days it’s not only companies and other organizations that have to continually get the word out in effective ways about their offerings. Individuals have to do it too, and the marketplace is crowded, confusing and noisy.