On the "books read" section of Ev Williams' GoodReads profile.
"I liked it." - Mark Zuckerberg
"Through Ender’s journey, you’ll learn how to capitalize on your strengths and those of your teammates, as well as exploit your adversaries’ weaknesses." - Tim Ferriss
"About a kid who is trained by the military to play video games [...] But he realizes at the end that the video games he was playing were an actual war." - Travis Kalanick