The Hollywood Reporter has an interview with Robert Kirkman (the creator of the Walking Dead comic book, and producer on the TV show) which a few hints about the future of the series. Probably the most notable information is that the earlier reports that they had forgone a writing staff in favor of having every episode written by freelancers is false:
We have a full writing staff; there are three full-time staff writers and a freelancer: Evan Reilly (Rescue Me), Scott Gimple (FlashForward) and Angela Kang (Terriers) and one freelancer.Darabont and [new executive producer] Glen Mazzara and myself are all working on the show. All that reporting about the writers being fired and going freelance, that was all something that never really happened.
That’s been discussed a little bit. Everyone involved on both sides of that are very anxious to make that happen; AMC is excited; Frank Darabont is excited; I’m excited. I know Stephen King and Joe Hill are excited. We’ll see if we can make that come together. I can neither confirm nor deny.
THR: When are we going to meet machete-wielding bad-ass Michonne?
Kirkman: Maybe Season 3. Frank and everybody involved in the show love her and we’re all very interested in working her into the show.
So we know they won’t get that far into the comic’s story line.