Robot from the Future
I believe it is time for this thread to be created. After the announcement on the 6th of June there was nothing until August 7th's announcement of Lycanroc Dusk forme. I will keep updating these posts as we get more information.
Currently we know very little.
Release Date is November 17th World Wide
Japanese and UK Nintendo Direct Announcements from 6th of June which include Solgaleo-N and Lunala-N (as we have called them).
7th August 2017:
Lycanroc Dusk Forme is shown to the world via Pokenchi and a Website update. It looks like this Lycanroc forme will be in the newest Pokemon Anime episode, so expect some more information soon. We also have Corocoro coming in the next few days, so expect more news then.
8th August 2017: Corocoro early scans have been leaked and they imply that Dusk forme will get access to both Accelrock and Counter. It will also have the ability; Tough Claws. Serebii is awaiting further higher quality scans before anything else can be reliably determined.
10th August 2017: It appears that Rockruff will be the gift in the same vein Munchlax or Torchic were. Only this specific Rockruff can evolve into Lycanroc-Dusk. This has been loosely confirmed by Serebii here: "Rockruff caught during regular play cannot evolve into Lycanroc (Dusk Form)." https://twitter.com/JoeMerrick/status/895503611471339523
11th August 2017:
A new trailer for Lycanroc Dusk forme has been released for Japan. Seems to cover the same info we already know about.
18th August 2017:
New video from the Pokemon Channel showing a "new" overworld image, the player speaking to Ryuki, Kahili appearing and also some environmental tidbits. We then got a video about Kommo-O's new Z Move; Clangorous Soublaze.
Comparison of old and new Alola islands, as found on Pokebip via Rapti:
13th September 2017 (14th in some Regions):
Nintendo Direct airs and gives us immediate information about Ultra Sun and Ultra Moon. It is heavily implied by this video that were will likely be four more videos released before launch of the game (probably weekly). A new Pikachu related to the Pokemon Movie is teased, as well as several new areas are show. A beach behind the Tide Song Hotel is shown, and Mantine appears to be a Ride Pokemon. Necrozma appears to be a much larger part of this games Story than in SM, similar to Giratina's presence in Platinum.Nintendo Direct information
Pokemon Youtube Channel with UB information and Lycanroc information
The four new updates (which I presume will be weekly):
Part 1 - The Key to the Story - Necrozma - The footage shown implies a showdown between Solgaleo/Lunala and Necrozma at the Shrine.
Part 2 - Charting new areas of Alola - Footage shows us the new area mentioned above and some more visuals of the Pikachu infested area. It also shows some new clothing options. It also shows us that we have a new way of getting our Starter Pokemon.
Part 3 - Bonuses - Lycanroc is shown using its new Z move, Splintered Stormshards. Lycanroc Dusk (From Rockruff) is your "Early Buyer" bonus like Munchlax and Torchic were before. Ordering the Digital Version gives you a code for 12 Quick Balls. Purchasing Gold or Silver on VC will gain you access to a special Celebi. https://i.imgur.com/uwtFja0.jpg This Rockruff is shown to have access to Fire Fang in Sun and Thunder Fang in Moon. It also has access to Happy Hour.
Part 4 - New Pokemon!? - Footage shows UB Burst and UB Assembly. UB Burst appears to use a new move, while Assembly uses Iron Defence.
There is also a special New 2DS which has a Pokeball Design which is available November 3rd.