I don’t have the “new iPad” but hey, I feel like I have a totally brand new device with iOS 5.1.
Because of this software update (from 4.3.3), I can now use iMessage. I no longer need to borrow someone else’s iPad to send messages via iMessage.
For me, iMessage was the main reason why I even bothered to update to iOS 5.1. With iMessage, my iPad is one step closer to becoming a gigantic iPhone.