You've probably seen the hubbub abut the orientation lock button on the iPad turning into a mute button. Well it's true. To lock the orientation of your iPad you have to double tap the home button to enter the app tray and swipe left.
Before you upgrade your device it's always a good idea to back up all of your data. This is especially important when you haven't synced your device in a while. While the chances of a error occurring and forcing you to go full restore are slim, it's always a good idea to backup your stuff.