We know that a lot of Marvel's bigger properties are licensed to other movie studios (Spider-Man, X-Men), so it's a no brainer that they are going to be looking for other characters to portray on the big screen.
"aliens who were put on Earth as sleeper cell aliens to eventually call back their race to take over the planet. Ultimately, the group of aliens fully assimilates and don’t want to cause war."
The project is currently out to writers with no release date set.
Interestingly enough, the race that helped to create the Inhumans, the Kree, are the enemies to the aliens rumored to appear in The Avengers. The Kree experimented on early humans and created a race of super beings that went on to form their own civilization.
Wonder if we'll be seeing Black Bolt and company in Joss Whedon's The Avengers? That would be a cool easter egg.