In case you needed a reminder: today is the day that Apple's newest operation system, iOS7, becomes publicly available for mass consumption. No worries about plugging your device into iTunes and continually pressing refresh, the update will be pushed out OTA (over the air) by Apple directly and your device should notifiy you at some point today about the availability. If for some reason you're not a patient person, and can't wait to be notified automatically, you can always manually check for updates on your device in system settings.
Good luck with your updates and, of course, make sure to backup your device prior to the change!