The only question is what will be the extent of Johnson involvement. Both Deadline and The Wrap say that he will be writing and directing Episode VIII and a treatment for Episode IX. Deadline says Johnson will also be directing the latter movie, while The Wrap says he will only be writing it.
While I do have to say that I loved Johnson’s Looper, the one concern I have about this is that Johnson’s typical tone is a bit darker than what you’d expect from a Star Wars film. I don’t know if this means that future episodes will be darker or that Johnson will be adapting his style to fit.
Even though Johnson is a skilled and talented director, the fact that Abrams is doing all the films is a bit disappointing. While changing directors mid-stream in the Original Trilogy did give us The Empire Strikes Back, it also gave us Return of the Jedi.
More on this as it develops.