Few notes from a book i've got which has a section on storyboards.
. All different aspects of making any film/animation like; sound, lighting, colour, story etc can't be considered alone which is why storyboard are so essential. which means storyboards make all the elements flow together by trial & error
. Rough guide lines to story boarding;
Film - 100 storyboards per minuet (more if the scene is complex
T.V - More than 100 because there shorter, have more action and scene changes
. Originated from the 1920's when artists would pin up gag ideas on their wall, this expanded into the job we see today which is called, gag man or storyboard artist
. Today the industry seems to do storyboards directaly on the computer through touch screen monitors and tablets (think initial storyboards are done with pencil and paper)