Zoom-in Online

Bill Buxton, at today's Microsoft Mix09 keynote, made an excellent point regarding design; namely, that as software people we often spend way too much design time focused on the layout and visual aspects of design -- what buttons are where, the set of input fields on a screen, etc -- and not nearly enough on the transitions between states.
He shows how integrating the time dimension - focusing on the state transitions, showing a network diagram relating pages to each other, working in a timeline - makes designs much more comprehensible and allows the designer to identify design problems early on.
Ideally the Microsoft Expression tools will follow this path increasingly.