Latino Review reports that Marvel has cast Josh Brolin as the voice of Thanos in GUARDIANS OF THE GALAXY with the strong likelihood of at least one additional appearance as the Mad Titan in a future Marvel Cinematic Universe film. That future movie would most likely be AVENGERS 3 given the mention of “Infinity Stones” in THOR: THE DARK WORLD. It appears very likely the MCU will put forth its version of the INFINITY GAUNTLET comic book mini-series in which Thanos was the lead antagonist.
Variety has also picked up this story, which Marvel has yet to confirm. GOTG director James Gunn is usually quick to shoot down bogus rumors and reports, so it’s worth watching his Twitter feed for the next few hours.
Thanos is as big and bad as Marvel villains come, so a commanding, weighty voice has to be required of any actor taking the role. Josh Brolin can certainly deliver that. While it would be great to hear Brolin as Thanos, it would be even better to see him in the role as well. Unless Marvel kept a big secret from us, it’s probably too late for us to see Brolin as Thanos in GOTG, but I will hold out hope for Brolin to sport some purple makeup and prosthetics in AVENGERS 3.