It's really not too clear how much truth there is to this, so I'd recommend taking it with a grain of salt until a report that doesn't originate from Latino Review is released. That said—according to Latino Review, the former governator himself, Arnold Schwarzenegger is in talks to portray the human villain in James Cameron's upcoming Avatar 2. They report this news in a very convincing way, too:
In terms of story, the first sequel will pick up after the events of the first film, when Jake Sully (Sam Worthington) permanently transfers his consciousness to his Na’vi avatar and begins a new life with Princess Neytiri (Zoe Saldana) after they defeat the human colonizers. [...]
Nasty humans, huh? Well guess what cool kids! We know who one of those nasty humans are going to be. In fact, according to top level sources, a bad guy human general is going to be played by someone who hasn’t worked with James Cameron in almost 20 years. Ready? It’s none other than…
…ARNOLD SCHWARZENEGGER! BOOM!
BOOM! No one saw that coming.
But seriously, this isn't totally implausible. Schwarzenegger and Cameron have previously worked together before, and Schwarzenegger has expressed desire to work together again. Plus, if production starts next year as is planned (the release date is currently sometime in December 2016), it seems like it would all work with Schwarzenegger's schedule. And, in Latino Review's defense, they have been right about a few things—maybe this is actually going to be a thing.
We'll have more this as it becomes available.
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