Here is a very brief video (confirming the new iPhone firmware?) that shows how you can move icons around in the Springboard.  I think it is neat to see the icons "wobble", indicating that they can be dragged and dropped where ever your heart desires.  Very slick!

video from iphone.technovinky.com

There is a very interesting article at Gizmodo that you should read talking about the effects on unlocks and Third-party applications.  Imagine that ... there is an effect on 3rd party applications.  I am so surprised! :)