One feature I find interesting is how easy you can add photos and videos you have already taken (as long as they were shot within 24 hours) on Insta stories. It is much easier than SnapChat memories.
But it will continue the curated content that Instagram is well known for. Already the stories I have seen on their flow much better than they ever could on Snap.
I think this is good because you will have those who enjoy one or another form of story telling. This is not the end of Snap at all, but just another option on sharing through social.