Avatar! It's basically a big, blue, 3D money-printing machine. The previous record for Blu-ray sales was held by The Dark Knight, but Avatar has come along and doubled it.
The Dark Knight set the first-day Blu-ray sales record of 600,000 back in 2008. Avatar sold 1.2 million copies on Tuesday. By Thursday that number had climbed to 2.7 million, surpassing The Dark Knight's 18 month sales total of 2.5 million. And keep in mind that these are sales of the bare-bones edition. We still haven't seen the deluxe or 3D editions.