So what is a Visual Novel? Well that depends on what direction you come from. From a static media perspective, the visual novel is a comic book with choices. From a video game perspective, its a graphic adventure game without an inventory to keep track of. They all have text and pictures. Most have choices to make, some tell a linear story (aka Kinetic Visual Novels) without choices. Most are hand drawn graphics. Some have voice over, music, sound effects, some pictures are animated.
I saw an article last week on a list of things that have nearly disappeared over the last decade. All of them are still around, they are just becoming archaic or obsolete. I suspect that over the next decade, there will be other things that are common today that will become archaic and decline over time.