Marvel Comics recently revealed that writer Matt Fraction would soon be leaving two series, Fantastic Four and FF. The reason revealed by Marvel Senior Vice President of Publishing (and editor of both titles) Tom Brevoort to CBR was that Fraction would be taking on the new Inhuman series, part of the upcoming "Inhumanity" crossover story. Taking over for Fraction on Fantastic Four is Karl Kesel, who has previously written the Fantastic Four and seems to have a good feel for the characters. FF, a new series that Fraction and artist Mike Allred began, will be written after Fraction's departure by Mike's brother, Lee Allred.
The last issues where Fraction is the main writer will be Fantastic Four #12 and FF #11. Fraction had story arcs planned for both titles and they will remain, only carried out by the new writers. Consequently, Fraction will be co-billed during the arcs, and the new writers (whether it's Kesel/Allred or other writers) presumably getting solo credit after those arcs have been completed. It sounds like the Fraction-created storylines will wrap up in both Fantastic Four and FF around issue #16.
In addition to Inhuman, Fraction is also writing the popular Hawkeye series for Marvel. Interestingly, he also has a couple of new creator-owned series with Image Comics. The latest issue of Satellite Sam, created with artist Howard Chaykin, was issue #2, which was published on August 7th. His series with artist Chip Zdarsky called Sex Criminals (not to be confused with Joe Casey's Sex, also published by Image) is scheduled to come out on September 4th. It's understandable why Fraction would cut back at Marvel rather than on properties where he retains ownership rights. Still, this will likely be disappointing to fans of Fraction's work on FF and Fantastic Four.