Amazon.com (AMZN) has had its fair share of critics, for its inability to consistently turn a profit. The most prominent bear case against Amazon is that although the company racks up impressive sales growth, it has to procure these sales with very high expenses. Add to that a generous employee-stock award program, and at the end of every quarter, there's very little in profits left over for shareholders. But Amazon had something to say to its critics. It released very strong fourth-quarter earnings. Revenue grew 15%, and Amazon even produced $591 million in operating profit. Analysts had expected no profit. Amazon itself forecast a range of an operating loss of $570 million to operating profit of $430 million. Clearly, Amazon's results were much better than expected.