Here's the trailer in HD
https://www.facebook.com/video.php?v=10152715877082734
A few things to note from that trailer, some of which are probably SPOILERS. Cersie recieves a box from Dorne. In it is a dead viper with Myrcella's necklace in its mouth. This is presumably from the Sand Snakes. After this, the trailer has shots of Jaime and Bronn in Dorne, likely sent there by Cersie to get back Myrcella.
That scene with the dragon coming out of the dark and setting someone on fire is likely Quentyns, though he's probably been cut and replaced with someone else that serves the same purpose of setting the dragons loose.
Also, Jon Snow is curiously absent from the funeral pyre at the wall. Maybe because its his body being burned? This would confirm his death in the books, unless the red woman protects him from the fire.
That wouldn't make much sense since Davos and Stannis are still present though. Maybe Jon is wherever that battle you see him in takes place? That means the pyre scene is Mances, or possibly Maester Aemon (makes more sense since it seems they all gathered out of respect as opposed to the burning cage scene in the books). That means Stannis burns Aemon for his kings blood while Jon is gone, which is phucked.
Speaking of Jons battle, it's likely Hardhome. Its filled with wildlings, and borders the sea. We also have a shot of wildlings and Watch pushing off into the water on the run from something which is probably wights and/or whitewalkers.
Then again, Emilia Clarke has warned for reaction videos. I can only see this really pertaining to Jon. Those present at the pyre are Davos, Stannis, Mellisandre, Alliser Thorne and Janos Slynt. Maybe Jon does get killed, and thats his pyre where he gets reborn as AA. If so, he probably gets betrayed at Hardhome by Thorne and Slynt. This would also mean we dont get Slynts awesome beheading, which would blow since it was good revenge for Ned.
We've also got a shot of (probably) Stannis looking over a map with flayed man sigils placed around. He's probably planning his march on Winterfell vs House Bolton. I don't think they would build that up this season and then put off the battle till next season like the books. Stannis vs Bolton will probably be close to the end of the season.
Also, we've got a scene of Jorah in the slave fighting pits. Later in the trailer, we have Dany, Missandei, Daario, and a forth person in the pits being protected by the Unsullied from slavers. The forth person looks a whole lot like Ser Jorah, which means he gets reunited with Dany this season. With the griffs cut, that makes spending much time on Tyrions voyage pointless. Varys is still sending Tyrion to Dany. He probably gets taken by Jorah quickly during his voyage, they get captured, and then separated as opposed to being kept together like in the book. Jorah gets sent to the pits and Tyrion does whatever he usually does.
The scene where Missandei kisses Grey Worm is also worrying. In it, Grey Worms eyes are open, but they're blankly staring at her forehead and he doesn't move. Grey Worm is likely dead.
Also, Sansas bathtub scene! Shes legal now, so hopefully we get her in all her naked glory. hnnnngggg