Good article in Boxes And Arrows offering a solution to the problem most Interaction/Experience Designers are having these days. Architecting a dynamic interactive experience fueled by Web 2.0 technology. Essentially, a wireframe approach offered up in a storyboard format including narratives in detail bubbles to help walk the viewer through them. The author, Andres Zapata, calls this "The Guided Wireframe Narrative".
I've had my teams working like this as well. We've used PowerPoint, PDF's and semi-traditional Storyboard outputs to achieve a similar goal. This is something all Interaction Designers need to take to heart. There's not always time to prototype. And static wireframes and sitemaps are not always adequate for RIA development—but there still needs to be structure, good experiences don't come out of thin air.
I would also add that we move faster to visual design—and not over complicate solutions or over think. When people see artifacts that tell a story, they tend to understand it better. It's not about throwing away our artifacts, it's about evolving them and using the right tools for the right jobs.