My X-Men and Spider-Man novels for Pocket were both timed to be promotional tie-ins to the movies, but they were both set in the comics continuity instead.
Ditto for my Fantastic Four novel. Technically, it was set in the comic continuity, but I always had the movie audience in mind when I was writing it. I wanted the book to be accessible to the casual reader who might be more familiar with the movies than the comics.
And, yes, it was no coincidence that the book was published to coincide with one of the FF movies . . ..