Amazon now employs a whopping 542,000 people and plans to hire thousands more (AMZN)

Ted S. Warren/AP Amazon's employee base swelled an astounding 77% from the end of June to the end of September. Theretail giant now employs541,900 people, up from382,400 last quarter and306,800 a year ago. It is one of only two companies in the nation to employ over half a million people. It's hard to imagine a company that already employed382,400 people could grow its headcount 77% in just three months. But that's exactly what Amazon did. At the end of September, the e-commerce giant employed 5...