How'd they change the character? Are you taking about them casting a black actor?
Like I said, I know nothing of the book, just saw a youtube video. But yes, that is the more minor change. The biggest change, that the youtuber expressed, were other features, such as blue eyes that were seemingly a big part of the character.
If they gave the black guy blue eyes, because, according to the youtuber, were such an integral part of the character, I wouldn't really have a huge problem.
Personally, I'm going to watch the movie, though not in theaters. So I really don't care cause I haven't read the book. So to me, it's just a movie, and I like both actors. But I do hate when I read a book, or like a certain comic book character and the actor to play them are different, so I sympathize with the guy who made the video, and those who've also been upset about.
For instance, I have zero issues with a black gay super hero. But spider man was neither black, or gay, so when I heard they were trying to make a black/hispanic, gay spiderman, I thought it was pretty pathetic. I also don't care for spiderman, so I wasn't watching it either way. It's the whiney changing of iconic character that pisses me off. Make NEW ones in the way they want.
In The Walking Dead, jesus is gay. No problem. In fact if some conservative group bitched enough to bully the characters in to making him strait, I'd be pissed off.
I liked a classic game called Teken. Well animal rights activists bitched enough to have them take out the fighting kangaroo. THAT pisses me off a lot. I'm not much of a gamer, but I love Zelda. Make Link a woman, because of all of the feminists complaining, and I will pretty much give up on games/movies/etc.
I'd bet my left AND right nut, that if they made a Mike Tyson documentary and cast a white guy, the black community would go NUTS.
Just keep fictional characters how they are in the novels and games, and make new ones. It's that simple. Find a story about your preferred character, and make the movie. OR make the story and then make the movie. The fact that everyone is trying to highjack cultural fiction icons, and make them a type of character that they deem "fair", or "justified" or whatever, only shows me that they don't give a damn about the story, OR the character. It's all spiteful BS for ego and revenge.