Unsurprisingly, Avatar has done extremely well during its home video run. In fact, James Cameron's movie has claimed the honor of best-selling Blu-ray movie ever, beating the previous title-holder, The Dark Knight. According to a report by Variety, 2.7 million Blu-ray discs were sold in the four days since its retail release in the US. (In comparison, The Dark Knight took 18 months to sell 2.5 million discs.)

Perhaps a testament to the growing demand for Blu-ray content, Blu-ray accounted for 40% of total home video sales for Avatar in the four-day window. That's a significant increase from the 25% market share The Dark Knight claimed over a year ago.

Avatar will most likely represent yet another sales benchmark when it is re-released on 3D Blu-ray next year. Thankfully, PS3-owning movie fans are already equipped with one of the few Blu-ray players on the market that will be capable of playing that disc.

This article was originally published on Joystiq.