In May, Forum One's Web Executive Seminar entitled "Putting Online Audiences First, Again and Again" focused on the application of user-centric techniques to capture audiences' perspective throughout the lifecycle of a redesign. One of the speakers, Kira Marchenese, gave an enlighting presentation on various approaches to usability testing.
My colleague, Andrew Cohen, has put together a great recap of her presentation entitled "Five and a Half Approaches to User Testing." It's definitely worth a read. Be sure to watch Kira's presentation for more details.