Well, everything's possible.
Five years ago I never would've put my money on a chance that "A Game Of Thrones" would actually be made, despite the fact that HBO bought the rights to the series. But guess what, now it's the highest-grossing show on TV.
I heard rumors of Momoa writing a script for the next Conan movie himself, as well as rumors that he doesn't even want to touch Conan with a 10 foot pole. At this point, it's all just speculation...
But I am nevertheless not very optimistic about a new Conan movie, or a TV series for that matter. Here's why...
First of all, Conan is not nearly as popular as it was in the '80s and '90s. And that's a fact. Yes, it's an immortal character, and has an army of fans. But back in those days Conan was a household name. Everybody loved him, even my mom.

Nowadays, it's all about superheroes and movies that play like cartoons (Avengers, Iron Man, etc.). They tried that stuff with Momoa's Conan and it flopped big time. You just can't turn Conan into a cartoon (and that's exactly what they did, in my opinion) and hope to resurrect the series. Fans will hate it, and young kids will not even pay attention to it because they're too busy meme-ing the s*** out of "The Avengers" on 9gag.
It doesn't matter what we think of Momoa's Conan. The movie flopped so hard it barely made back it's budget. It damaged careers of everyone involved, maybe even destroyed them. No one in his right mind would touch a Conan movie project after that. And before anyone starts saying "Sure, the movie didn't make a lot of money, but..." But nothing! Money is the only reason they make movies in the first place. They're not making it so they could get thumbs up from us, no matter how sophisticated our taste might be.
I'd love to see a Conan movie done right, naturally, but the only hope for Conan I see is in a form of a TV series. But even there lies a danger that people might just see it as a "Spartacus" and "Game Of Thrones" rip-off.
Unless they hire Mark Finn and force feed him cough medications, eh?

Then we might have an awesome Conan adaptation we all deserve.