This cinematic focuses on Saurfang's reaction to the Burning of Teldrassil. It also features a young troll nicknamed "Zappy Boi", who first appeared in the Battle For Azeroth trailer.
The cinematic is quite well done. Technically excellent and a nice look at the Horde. It's somewhat surprising that they went for a full cinematic here, as those are usually reserved for trailers.
If there is any problem here, it really harkens back to an old post I wrote, Alliance vs Horde Storyline Favoritism. In that post, I wrote:
That sets up two stories: a civil war within the Horde, and the Alliance attempts to finish Garrosh. Of those two stories, the civil war is always going to be the more interesting story.You can see the same pattern repeating. The civil war story is more interesting, and has more focus than the other story. We will see what Blizzard does with the Alliance though. If they will introduce an internal conflict for that faction.
A lot of people are predicting a repeat of Pandaria. At the end of the expansion, Sylvanas will become a raid boss and new Warchief will be chosen.
My prediction, however, is that Sylvanas stays Warchief throughout the expansion. The Horde rallies behind her, and unlike Garrosh, she does not turn on them. I think Blizzard will keep the faction war "hot" for the next few years, and the best way to accomplish that is to leave Sylvanas as the Horde leader.