It was announced as twelve so I guess they're splitting it into six and six. The vast majority of Netflix shows are all at once but it seems like they might be starting to do chunks of a season at once for more complicated shows - Baz Luhrmann's show The Get Down is reportedly very expensive and difficult to produce and it is also getting half a season at a time. Makes sense that something like Black Mirror, with different, sometimes high profile casts and directors each episode would be something they would want to release in parts to get some of it out there quicker.
Six in one go is already nearly doubling what we already have, I'm fine with the split and waiting for more.
Episodes: "San Junipero” with Gugu Mbatha-Raw and Mackenzie Davis directed by Owen Harris “Shut Up And Dance” with Jerome Flynn and Alex Lawther directed by James Watkins "Nosedive” with Bryce Dallas Howard, Alice Eve, and James Norton directed by Joe Wright "Men Against Fire” with Michael Kelly, Malachi Kirby and Madeline Brewer directed by Jakob Verbruggen “Hated In The Nation” with Kelly MacDonald directed by James Hawes “Playlets” with Wyatt Russell and Hannah John-Kamen directed by Dan Trachtenberg
I'm not familiar with a lot of those names off the top of my head, but I will definitely be looking them up.
Interesting note: Mike Schur and Rashida Jones wrote "Nosedive" and Dan Trachtenberg wrote the episode he directed.
I'm imagining Shut Up and Dance to be some kind of hell episode where people are forced to listen to that Walk The Moon song forever and I love it.
Images from two new episodes, if you're into that kind of thing First Look: Black Mirror Season 3 Images from Netflix
More excited for this than any other show/movie in recent memory... since maybe Arrested Development S4.