This disc uses seamless branching to offer three distinct ways to watch the film:
The version seen in theaters in December 2009.
The longest version, adding 16 minutes to the theatrical runtime. It features an exclusive alternate opening on Earth that provides deeper context for Jake Sully's life before Pandora. Technical Specifications
Includes approximately 8-9 minutes of additional footage, including the "Sturmbeest Hunt" and expanded battle sequences.
According to technical reviews from Blu-ray.com and High-Def Digest :
The in 1080p is a comprehensive three-disc Blu-ray set released in 2010. It is widely regarded by enthusiasts as the definitive high-definition home release of the film due to its inclusion of three separate cuts and over eight hours of supplemental material. Movie Versions (Disc 1)