Activision says that sales of Call of Duty: Modern Warfare 3 have surpassed $1 billion in just 16 days — a record that Avatar set in 17 days — while adding further evidence to the fact that COD basically sells itself. Activision's consistently compared the sales performance of COD with major Hollywood releases over the years and with good reason — Call of Duty: Black Ops and Call of Duty: Modern Warfare 2 also reached the billion-dollar milestone, though just not as quickly. When Modern Warfare 2 was released, it edged out the first-week box office sales of Harry Potter and the Half-Blood Prince and The Dark Knight. When a billion dollars in sales can be measured against a stopwatch, we don't blame Activision for cashing in every year.