The Squad Zero emblem has apparently been revealed aswell:

Here's the full overview of the 3 specials though with some things I've missed out:
Gotei – 13
First Squad & Yamamoto Genryuusai Shigekuni:
* He only has his right arm now.
* He has some inner, unseen changes.
Second Squad & Soi Fon
* Soi Fon’s arm has been healed.
* Her hair changed a little.
Third Squad
* Rose is now the captain of third squad.
* Kira is still vice-captain of third squad.
* Kira's Bankai "feels a bit gross/disgusting"
Fourth Squad
* Unohana Retsu will fight.
* Her zanpakuto’s true form will be revealed.
* She will unravel her braid when she fight.
Fifth Squad
* Shinji is now the captain of fifth squad.
* Hinamori is still vice captain of fifth squad.
* There will be a mutual relationship between Shinji and Hinamori.
Sixth Squad
* Renji became more wild.
* Byakuya became prissier.
* Renji’s bankai changed.
Seventh Squad
* Komamura’s clothing has changed.
Eighth Squad
* Kyouraku will release his bankai in the upcoming fight.
* His flowered haori has a story.
Ninth Squad
* Kensei is now the captain of ninth squad.
* Hisagi is still the vice-captain of ninth squad.
Tenth Squad
* Hitsugaya perfected his bankai.
* There's a chain now attached to his Bankai's sword.
* Rangiku's past will be significant to when Hitsugaya started as a Shinigami
Eleventh Squad
* Kenpachi’s story of becoming captain will probably be told.
* Yumichika's strength rivals Ikkaku's - "Kubo has an idea for his Bankai"
* Ikkaku wears an armour equipment on his shoulder with the word dragon on it
* Possible Yachiru battle scene
Twelfth Squad
* Mayuri has a new appearance.
* Mayuri's research of the bodies will be his main role in the new arc
Thirteenth Squad
* Ukitake is still sick but will recover.
* Rukia is now the vice-captain of thirteenth squad.
Hueco Mundo & Arrancars
The below ones are all according to what Kubo said:
* The arrancars may show up again.
* They will show up as a group if they come back.
* Grimmjow might be a nakama.
* Nel probably will appear again as well.
Extra Informations
* The Lost Agent Chapter was based on Sado.
* The new battleground is underneath somewhere, unexpectedly close.
* Kubo said he wanted to draw a “Palace of Ice.”
* Many mysteries will be revealed during the final arc.
* The meaning of true blood, which Arrancars talked about.
* The relationship between Isshin and Ryuuken
* The psychical resemblance between Ichigo and Kaien
* Spirit King
* Squad Zero
* The relationship between Urahara and Yoruichi
* Hiyori’s fate
* The truth behind Masaki’s death
* Aizen will (probably) return
* Ichigo's birth