I knew a few things about the movie before the trailer was released. The biggest issue was how the movie was going to deal with the death of Chadwick Boseman who had played the titular character so well before. Disney and Marvel said that they were not going to recast the role of T'Challa (Black Panther), but that they would likely pass on the mantle of the Black Panther to another character. This had led me to wonder how they were going to handle the death or disappearance of T'Challa. The answer is: respectfully and powerfully.
I also knew that this movie would introduce one of Marvel's oldest characters: the Submariner, Namor. Although lesser known, this is the character on which DC based Aquaman. What was interesting to me were the rumors that they were going to tie Namor's Atlantian culture to Mesoamerican traditions. In short, those rumors are true.
Now, as much as I liked the original Black Panther movie, and despite it being groundbreaking in so many ways, it is not my favorite MCU film, and I was not certain that I would want to watch the sequel in the theater. However, I watched the trailer yesterday [which I am linking below] and found myself unexpectedly tearing up before it was over. I immediately had to watch it again, and my eyes still welled up. I saw that Eric Voss of New Rockstars (my favorite host and channel for spotting Easter eggs and references) had a reaction video to the trailer, so I watched that and found that I was not the only person moved to tears by this amazing tribute.
Since then, I have watched the trailer dozens of times, often by watching other commentators' reactions to it. The cinematography, the music, and especially the powerful lines by the outstanding Angela Bassett (playing Queen Ramonda, T'Challa's mother) all come together to form an amazing tribute, a message of both mourning and hope, and the greatest movie trailer I have ever seen. I don't know if this movie will be able to live up to my expectations at this point, but this trailer alone is a masterpiece. I am definitely watching this movie in the theater.
Link to YouTube video of the official teaser trailer for Black Panther: Wakanda Forever