It depends on what you do. Wedding guys would probably appreciate IS as they are often shooting in low light. If you shoot on a tripod, as I do for 95% of my work, IS is useless.
Another thing to consider about IS is that it doesn't slow your moving subject during your 1/4 second exposure. If you shoot people, as long as they are actually alive, they will be moving about! IS is nice on longer lenses, where camera shake is a bigger problem at even medium shutter speeds.
JJ