I'm pretty sure he's focusing his time now on Futurama.

The internet seems to be under the impression that Matt Greoning writes, directs, and draws every single Simpsons episode himself.

In reality, he hasn't had much of an active role since he started developing Futurama in 1998.

Internets...I hate them so much!

The Simpons we knew and loved so much were the creation of many writters, Matt always had the most minimum input in the scripts as far as i know. Everyone from Conan to David Cohen (who later moved to Futurama) are just some of the many builders that made the show so good. These days i have no idea who is writting the show, but they certainly have no clue of what they're doing.

The current writers are a bunch of people who grew up watching The Simpsons which stunted their developing senses of humor and caused the joke recursion to nearly destroy the universe every time they put pen to paper (er, dictate to iphone.)

They also made Maggie into Howard fuckin' Roark in an episode.