"Avatar" is already the year's top-selling home entertainment title after just four days in release.

Consumers snapped up 6.7 million copies of the first "Avatar" DVDs and Blu-ray Discs, which are 2D versions of the action fantasy offering no bonus features. "Avatar" sales quickly have outpaced the 6.5 million units sold of Summit/Universal's "The Twilight Saga: New Moon," which had been 2010's hottest disc release to date.

Fox Home Entertainment began selling the "Avatar" discs Thursday to coincide with Earth Day. The James Cameron epic marked a format record by moving 1.5 million Blu-ray copies in its first day on store shelves.

FHE will release special edition versions of the James Cameron epic in the fourth quarter, with those versions set to include special features of the sort normally included on home entertainment discs. A 3D Blu-ray version of "Avatar" will be released early next year.