Amazon ceo Jeff Bezos wrote his annual letter to shareholders and, as with last year’s letter, he focuses on the trinity (or “three big pillars”) of Prime, Marketplace, and AWS. (The last time he mentioned readers or Kindle was two years ago.) Prime membership grew 47 percent growth in the US last year and counts “tens of millions of members worldwide.” And “close to 50 percent of units sold on Amazon are sold by third-party sellers” (which includes publishers who sell ebooks on an agency basis). This year’s letter also speaks vaguely at length about “corporate cultures,” following criticism of Amazon’s work environment: “For better or for […]