Amazon's reason for the inavailability of the set is because it is "currently under review." The likely reason stems from an ongoing legal squabble between Marvel and Rimowa, the company who created the metallic briefcase that the set is modeled after. According to the lawsuit filed on August 1, 2012, Rimowa claims that Marvel Entertainment and Buena Vista Home Entertainment have conducted trademark infringement, unfair competition and trademark dilution. More specifically, Rimowa states that Marvel nor Buena Vista/Disney sought permission to use the trademarked horizontal bands that give the metallic cases their unique look.
No one is sure what will happen at this point. The lawsuit could continue on into the courts, which would significantly delay or cancel the Marvel Cinematic Universe: Phase One - Avengers Assembled Blu-ray set as it appears today. Marvel and Rimowa could settle out of court between now and September 25, giving us the sets as-is on the original release date.
Marvel and Disney could also opt to alter the packaging and release the set at a later date. In my opinion this is a worst-case scenario.
What should you do if you have already pre-ordered Marvel Cinematic Universe: Phase One - Avengers Assembled on Blu-ray? I wouldn't cancel it, that's for sure. There's a chance that those who pre-ordered will still get the set regardless of the lawsuit. Or, the lawsuit could not be involved at all and Amazon has sold through their allotment. You just never know.
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