MTV News thinks that Vin is secretly playing Thanos, in a statement:
And then there's the Thanos question. The death-obsessed, purple elephant in the room. There hasn't been a word on who will play the villain teased at the end of "The Avengers," despite Gunn and Marvel Studios co-president Kevin Feige confirming that he'll be present in "Guardians of the Galaxy." Thanos could in theory be a CGI character, but Gunn's usage of practical makeup effects and his cameo in "The Avengers" has us thinking otherwise. Before he posted the image of Groot, Diesel hinted that he could play Vision. So if this all turns out to be a ruse and he is actually playing Thanos, it wouldn't be the first trick he's played on Marvel fans.
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