I'm generally interested in reading more about how introverts are critical to a good team and how they can be the difference makers in several situations. The recent increase in these articles is clearly justified given that our culture tends to naturally value the contributions of more extroverted leaders than introverted ones, at least on the surface. Further, extroverts, or even ambiverts (people on the middle third of the introversion/extroversion spectrum), often have a hard time understanding introverts, communicating with them, or even being really aware of their contributions.
Even though I'm sure that Susan Cain wrote her 2012 book Quiet: The Power of Introverts in a World that Won't Stop Talking as an effort to make a case for the value of introverts in the professional world, I tend to find it much more useful as a tool to help people on all parts of the introversion/extroversion spectrum to better understand and leverage the more introverted people around them.
Cain's book starts by outlining what she calls "The Extrovert Ideal" - basically, the parts of American culture that value extroversion over introversion. Then she goes on to explore several ideas, including whether or not extreme introverts can ever become capable public speakers (yes), whether introverts often act in ways beneficial to business when extroverts don't (again yes), and whether there are successful cultures that value introversion more than extroversion (still yes). But the best part of the book, in my view, is near the end where Cain gives practical advice on how to better communicate with your "opposite" on the spectrum and how to successfully raise "quiet" kids in a world that often loves loud ones.
Having said that, Quiet is not a perfect book. One of the biggest shortcomings is the oversimplification of how much people vary on the introversion/extroversion spectrum. In fact, as with most normal or near-normal distributions, there are relatively few people that are extreme introverts or extroverts and most people fall somewhere in between. In fact, labeling someone as simply "introverted" or "extroverted" if they fall on that third of the spectrum is likely inaccurate in most cases. It's unwieldy, but it is much better to think about people who are "more introverted" or "more extroverted" than average. There is also not enough consideration given to the chunk of people in that middle third of the spectrum that are now sometimes called "ambiverts" - people who display both introverted and extroverted tendencies depending on situation or mood. Finally, even though I think that more extroverted people will benefit immensely from reading this book as a way to understand the more introverted people in their lives, the book often reads a bit too much like an attack on extroverts than it does advocacy for introverts -- unfortunately, I think that will turn off some people that would benefit from its ideas.
Regardless, I have recommended Quiet to more introverted leaders I have coached, especially when they are looking to find their footing in a new position or who may be needing to find some tools to becoming a more effective speaker. I also recommend it (with the caveats outlined above) to more extroverted people who want or need to understand colleagues or family members who are challenging for them. There is plenty of good advice, thoughts, and insights for people on all parts of the introversion/extroversion spectrum to make the book worth reading.