just use left/right arrow keys with the video paused.
It works better within the Youtube site and when the video is (almost) loaded.
I've tested it and the individual pics are really amazing!!
NOTE: you must click multiple times the keys in order to advance to a new picture, as there is not a direct correspondence between frames and images.
It's amazing what they managed to squeeze in -- if you added something from one religion you'd get folks saying "but what about..."
The best thing about this is that it makes you think what YOU would include / exclude if you were doing your own version...
if you single step thru it, there are quite a few "iconic" photographs - Time / Newsweek cover type stuff - Kent state, the girl in the road in Vietnam, etc. If everyone included everything they wanted, it would run a lot more than 2 minutes! I'd guess they made it so annoyingly fast to make you go back later and look at it again in more detail.