How does The Incredibles NOT have a sequel film yet?!

Of all the Pixar films, The Incredibles was the only one that I thought deserved more expansion! Cars, Monster's Inc, Nemo, and even Toy Story all ended nicely with their own closure. But The Incredibles has plenty more things worth exploring! Is it just not as popular as the other films?
With that aside, I'm glad for the title change. The idea of Marlin losing Nemo a second time is ridiculous. And perhaps we'll be able to see a whole new adventure that fleshes out Marlin and Nemo's relationship.