Matt Buchanan, The New Yorker:​

In April, 2011, the Google co-founder Larry Page took over as C.E.O. Besides moving to streamline Google’s increasingly sprawling scope as a company, he immediately launched Project Kennedy, an initiative to give all of Google’s products a more consistent look, so everything would be easier to use.
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​Nearly a year later, the crisp design cues of Google Now and the Kennedy Project have swept across Google, and cards are set to become one of the dominant ways in which Google presents certain types of information to users. In other words, a card will be the atomic unit of information display across all of Google. In addition to Now and Google’s Glass wearable computer—where all information is displayed as a card—they have started appearing across a multitude of Google's services and applications, like the Play Store, Gmail on iOS, and mobile search and Plus, to name a few. And today, cards are invading two of Google’s most important products outside of search, with a dramatic design overhaul of both Maps and its Plus social network. That change might seem minor in some ways, but there are profound implications in the proliferation of cards, given that they will become the way that billions of people consume and digest bits of information they’re seeking from Google over the next few years.