So what is next

[dspringer1]

is the next book Butcher writes going to be another Dresden, his alternate series (with the flying ships) or the strongly hinted YA series focused on Maggie. 

[Mira]

is the next book Butcher writes going to be another Dresden, his alternate series (with the flying ships) or the strongly hinted YA series focused on Maggie.

I wish he'd focus more on completing this series, he has enough on his plate.

[Kindler]

I think the plan was for the next book to be The Olympian Affair. The YA series was (last I heard) going to be co-authored with his sister. The way he described the process sounded as though they would collaborate on an outline and he'd move on (meaning his sister would do the writing). Kinda like what RA Salvatore did during the War of the Spider Queen series in the Forgotten Realms (though hopefully something better and more evenly characterized).
Only thing we know for sure is that Mirror, Mirror was pushed back, and another full novel has been added to the main series (currently titled "Twelve Months).
https://www.jim-butcher.com/faq/upcoming-works
That hasn't been updated this year yet, but it claimed that the next novel Jim is writing is The Olympian Affair, book 2 of the Cinder Spires.

[CrusherJen]

I wish he'd focus more on completing this series, he has enough on his plate.

I'd love to get the books faster too... but if I'm remembering right, Jim's said in interviews that writing other series helps him recharge his creative juices and come back to the DF with better energy. If he only wrote Dresden books, he'd probably be burned out by now, and we'd really be out of luck.

...plus I really loved the Codex Alera series, and I hope he goes back to that world eventually. I haven't started the new series yet, but I'm looking forward to it.

[Mira]

I'd love to get the books faster too... but if I'm remembering right, Jim's said in interviews that writing other series helps him recharge his creative juices and come back to the DF with better energy. If he only wrote Dresden books, he'd probably be burned out by now, and we'd really be out of luck.

...plus I really loved the Codex Alera series, and I hope he goes back to that world eventually. I haven't started the new series yet, but I'm looking forward to it.

That may be true, but six years between books?  Really?

[CrusherJen]

I don't remember all the details at the moment, but I heard there were a lot of real-life events that delayed Peace Talks-- a divorce, building the new house, getting remarried-- so that six years between books wasn't typical. I'm hoping, as we all do, that we won't have to wait so long for the next book of the DF.

[TrueMonk]

If we discount 2016-2019 where Butcher did not publish any books, he published a Dresden files book every year 2000-2015 except, 2005 and 2014. At the same time he published a book a year in Codex Alera from 2004-2009, so I think the formula is working very well for him. To get the overview myself I made the attached picture.

[Conspiracy Theorist]

I'd love to get the books faster too... but if I'm remembering right, Jim's said in interviews that writing other series helps him recharge his creative juices and come back to the DF with better energy. If he only wrote Dresden books, he'd probably be burned out by now, and we'd really be out of luck.

...plus I really loved the Codex Alera series, and I hope he goes back to that world eventually. I haven't started the new series yet, but I'm looking forward to it.

If only there was some way to keep Jim sequestered in his cabin, unable to go to conventions or book tours or indeed have any other outside distractions for the next 6 month so all he can really do is sit down with his dog and cat and write the Olympian Affair and Twelve Months. Oh wait....

[Dina]

 
Yes, as far as I understood, the next full book is The Olympian Affair. Even when I really, really want to read more Dresden, I am not complaining. I miss my Gwen.

[heidi_storage]

I think the plan was for the next book to be The Olympian Affair. The YA series was (last I heard) going to be co-authored with his sister. The way he described the process sounded as though they would collaborate on an outline and he'd move on (meaning his sister would do the writing).

I'm glad to hear it. I love Jim, but I don't think he's good at writing Maggie--even in "Zoo Day" she doesn't sound like a traumatized child to me. She's not nearly enough of a pain in the butt for even a child raised in nice, typical surroundings, and kids who have been through rough times often have behavioral issues. I hope his sister can make Maggie a little less ideal.

[Dina]

I did not like Zoo Day either.

[KurtinStGeorge]

I've seen one interview Jim did about two months ago where he specifically mentioned that he was working on the Olympian Affair.  I think he even went into the plot a tiny bit further than I had heard before.  Something about talking cats on Spire Olympia.  It wasn't anything major or very specific.  I just thought it was good that Jim was already making progress on the next book. 

In the old days Jim might Tweet the novel's expected word count and what percentage of that count he had completed, and do so on a fairly regular basis, but he doesn't do Twitter much anymore.  Of course, maybe that's a good thing.  Less time on social media and more time writing.