I'm actually surprised that there hasn't been any kind of Invincible movie rumored, let alone made. The comic has been around forever now, fucking Kick-Ass got a movie AND a sequel and Walking Dead has a TV show AND a spin-off.
You'd think that with Superheroes as big as they are, and Kirkman's other major property being the success that it is, people would have jumped on the opportunity to adapt it. People obviously read it since it's still going and has had like a million crossovers by now.
Yeah, that surprised me too. I imagined that with the success of The Walking Dead, and the train that is superhero movies not coming close to stopping, Kirkman would have leapt at the chance to turn some of that goodwill and industry connections to Invincible.