Apple have just released iOS5 for all to download, So if you an iPhone 4, 3GS, iPod 4th gen, iPad 1 or 2 nearby then you can download the update and update your iPhone/iPod/iPad right now, The iOS brings such features as pull down notifications, Twitter integration, iMessage, Find my Friends and of course the new iCloud service that was just launched by Apple. There is also the lock screen camera which allows you to launch the camera from the lock screen.
Source: Apple