My Take
Yes, I think it's something different. Many of us have hit the point when we've seen and used so many PowerPoint and Keynote presentations, the themes and layouts are like a second nature, and recognizable like old friends. Haiku Deck offers novel fonts, a striking visual "look," and some helpful features. The image search suggestions are nice, but it's annoying to have sign up for an account/ sign in. It's not as manipulable as some of the old stalwarts, doesn't offer as many features, but for something new that the kids haven't seen before a hundred times, it works.
How I Use It
I haven't used Haiku Deck for extensive presentations, but I have used it for quick warm-ups and discussions.