David Ogilvy taught us junior O&M'ers years ago that all good advertising and marketing solutions began with a study of the consumer. I think it's fair to say that this still applies to virtually all aspects of marketing today, especially the business of media selection.
People today spend 1,555 hours annually watching Television, 190 hours surfing the Net. They spend 975 hours listening to Radio, 19 hours with Interactive TV and wireless content.
Perhaps that's why so much of what's called 'new' media today are simply new platforms for television, usually in a smaller and/or less convenient form: sports on mobile phones, anyone?
Begin media planning with a clear understanding of how your customers and prospects use the media today, and allocate your sales messages accordingly.
Note: Media usage data from the Statistical Abstract of the U.S. Census Bureau.