Denis Pelli at his NYU website:
Sometimes, seeking publicity is condemned as self centered. I think this criticism misses the point. It’s good to like one’s work, and it’s a mistake to suggest that getting publicity is selfish. Today, more and more, we need to convince the public of the merit of our work. For example, if we are to help recruit undergraduates, they and their parents need to hear of us. When we publish in journals, we reach only our professional colleagues. To reach the rest of the public, we must go beyond the journals: either through publicity about our articles or by publishing in other media.
In my own experience, trying to get noticed beyond journals has been scary, frustrating, and hard. Which efforts matter, and which don’t? With journals, we’re insiders. With other media, we’re outsiders knocking at the door. And the rules are very different.
Twitter has many fans and many critics. I wrote an article in Seed about the future of literacy and publishing which was widely tweeted, attracting ten thousand visitors and a thousand Twitter and blog links (including the New York Times). That’s a lot of people reacting to my work, but, of course, it’s mostly the lay public, not university colleagues. So, it was exciting, but I couldn’t figure out the equivalent in the real currency of journal citations. I finally realized that I was asking the wrong question.