You've heard of software-as-a-service; I believe a big change needed for the 21st century is to see every piece of communication as a service.
What does software-as-a-service do? It enables people to do things for themselves.
When you think of how to deliver a message, how can you make that message an experience, a facilitator that lets people do something that's useful or helpful for themselves?
For example, a bus-stop-ad for hearing awareness week had a way to check if your iPod was turned up too loud (just put your earbud into a sensor). It was information, but then it enabled you to make that information personally relevant to you.
How can you make your advertising or marketing communications more useful?