Looks like Dr. O'Malley is dead.
When we last saw George O'Malley, he had been flattened by a bus. So, writing him out of the show shouldn't be a problem.
Could Knight's good pal and former co-star Katherine Heigl be next to exit? Heigl famously derided Grey's writers when she withdrew her name from Emmy consideration two seasons ago. Rumors of her departure from the show have followed ever since.