I keep seeing new projects that implement things that Emacs and Org mode already do incredibly well. I guess it's a testament to how steep the Emacs learning curve is, or perhaps how ugly the defaults look.
You have ox-beamer, which lets you write your slides in Org-mode, and export using LaTeX and Beamer, which look pretty great. You can also use org-reveal, or org-re-reveal to make some visually very attractive presentations with reveal-js. And finally, if you want to actually have the presentation run inside Emacs, you can use dslide[0] which looks really nice, and leans heavily on org-babel.