There does not seem to be any indication to the user of what they're supposed to do to get the next slide, or even that there is a next slide.
EDIT: Well, OK, now that I maximized there is. But there was no indication that I was missing content to the left or right either. I appreciate simplicity but you gotta give first time users something to get them going.
But this is not for users. These are slides used in a talk served by presentation-oriented software. The user of the software is the person writing and doing the talk, not us. The fact that it's HTML5 makes it very easy to share with people who have not seen the talk, but the primary purpose of the tool is to help the speaker, not late readers.
EDIT: Well, OK, now that I maximized there is. But there was no indication that I was missing content to the left or right either. I appreciate simplicity but you gotta give first time users something to get them going.