1) In Use…
On the one hand, I find the FluidMoveBehavior in Blend very simple. When an item’s layout changes I can use the behavior to have the item animate from its previous layout position to its new layout position rather than having the change be instantaneous.
In truth, I think the change is still instantaneous but the Behavior does clever things to apply transformations to the item from its new position to make it look like it’s travelling to that position from its previous position.
Read more: Mike Taulty's Blog