Just as many of us expected, Civil War will be the point at which the Marvel Cinematic Universe goes to the next level.
We have been waiting for a long time for Spider-Man and related characters to finally come over to the Marvel-verse. Right now, Spider-Man rights are currently held by Sony, who have been doing the various Spider-Man films. Instead of getting the rights back they have made a deal with Sony to have Spider-Man appear in their Marvel Universe films, which essentially will also put the new Spider-Man movies that will come out into the Marvel Cinematic Universe. This is something they could try to do with Fox, but their interpretations of the X-Men and Fantastic Four are too divergent for the Marvel Studios movies.
Right now we are expecting three new characters to be introduced in Civil War, as revealed by the screenwriters. These include Black Panther, which is preparing for his own film in 2019. This will also have his father die in the movie, which was a major death announcement for the film. The film will also include Spider-Man, as played by Tom Holland, and Aunt May, as played by Marisa Tomei. This caused a bit of a controversy because of the young Tomei playing Aunt May, but many see it is a welcome change.
So what else can we expect from Captain America: Civil War? This is going to really be where Marvel Studios hits their stride and makes the universe they have been building for the better part of a decade really work in the way that comic fans hope.