Allow me to qualify my following thoughts by saying that I am extremely biased.
Pardon the cliché, but when I saw the original movie for the first time, it blew my mind. This film defined the genre for me. Heck, it defined movies for me.
Every movie I've seen since has been held up to this one to see how close they came to challenging and entertaining me as a viewer.
The original is perfect. I don't think my bias is showing in that description. It has no superfluous scenes. It has no sharp edges. It is art, frame by frame.
So, this live-action version is going to come out and I'm a little wary.
I don't care that they cast a white actor to play the Major. She's a full body cyborg, it can be rationalized. While I don't rate Scarlett as an actor, I'm sure she'll do an adequate job with what she's given.
But I'll echo what has been said before: She's too human. The Major is suppose to show very little emotion.
I suppose my main concern is that the, albeit complex, themes of the original will be dealt with in a very hamfisted way. I am not confident that a Hollywood movie with a high-profile actor can deliver on that front and that we'll get some Matrix-esque action-fest instead.
Furthermore, I don't really like what I've seen in the teasers. MarkB mentioned that the cityscape works better in the live version. I see it differently. The contrast in the original makes it look like we're viewing it from inside someone's head. The window has a digital quality to it to build up the theme of reality vs. simulated reality. In the live-action version, the background blends in with the foreground, putting the focus on the Major and the Matrix plug she pulls from her brain. Maybe that's something that still needs to be adjusted in post.
I disagree with Goldomark's assessment that GitS is more about aesthetics than it is about character or plot. The whole movie is the Major trying to figure out who she is.
Also, I'm worried about these teaser shorts. I've had bad experiences with movies that put out a lot of extra content before a movie comes out. Prometheus did it, Suicide Squad as well. I don't know if I'm confirming my own bias here but movies that add a lot of material before it comes out generally leave me with a bad experience.
An on a last, optimistic note. If anything, I hope this movie points new audiences towards the original and the series.