At the risk of categorizing African Americans, they seem to really be into batshit insane power level type superhero stories. I always see black dudes playing Street Fighter and shit. They seem to really like DBZ. Not that other groups don't like them as well, but African Americans really seem to gravitate towards that kind of stuff.
Likewise, in the comic book world, I've noticed they like similar stuff. When I worked at an LCS in St. Louis, we had probably 45% black customers, and they almost exclusively read things like The Hulk, Superman, and Justice League (as well as events - though they were a lot smarter about those than whitey and knew which ones were worth picking up).
I think it's mostly just the "Ooooh shit! They did that!?" factor.