Cathryn and all,
Most or all of you probably know this, but the animation may not be a good idea to show it that way; the motions are probably exaggerated by tens of thousands of times. Whether Hayward is most dangerous depends on whether the simulations of 3D ground motion from San Andreas earthquake for Los Angeles basin are correct. The engineers are confident that if the simulations are correct for ground motion, many of the taller building will collapse.
Chris