its a lurvely lookin site, when you use a dynamic blur filter in flash while having a lot of other things happing at the same time (such as the animations and bars that follow the mouse) it chuggs along a bit, it seems that it slows at the end cos it looks like it has an easing effect on the transition from blur to sharp (it sharpens faster at the end) this is when all the proceesor power is required and therefore seems to chugg or jerk at the end.
Older pcs or macs will run slower also as macs always run flash slower at the high end of animation/processsor requirements.
Excuse the babble, bit hungover this morn and it made sense to me!
Happy new year n all that!