Have no fear, Geo from Twilighters has a video that explains it all.
EDITED: We noticed a couple of minor corrections/additions to the info Geo provides:
- The Walmart DVD has special features: audio commentary, three music videos and the five extended scenes.
- The Ultimate DVD Giftset (with the soundtrack, watch, etc.) is only available at Costco.
- The Ultimate Blu-Ray Giftset is available at Amazon but not until May 5.
- The single disc Blu-Ray is only available at Best Buy. It’s the same content as the national 2-disc DVD.
- Target has the only 2-disc Blu-Ray with the same items that Geo talks about when she mentions their exclusive 3-Disc DVD.
- The Blu-Ray versions will have BD-Live (that cool feature where you go online for content).