Some people surf with graphics off. Some people use text-mode browsers, VGA 16 colour graphics, etc. Dont shut these people off. One good image is worth three bad ones. Use good, catching images on your pages.
Information overload happens for people as it does for machines.
Some graphically intensives sites actually have so many images that most of them go unnoticed by the user. Use few images per page. Most browsers are configured to download 4 files simultaneously. Keeping the number of images under 4 helps the page download faster. Keep images small.