iTunesHelper was removed in a previous software update, I think it was OS X Lion. You shouldn't need it for anything anymore.
Edit: My bad, it is still there, it just isn't in my login items, you can re add it if you want to.
Find your iTunes application, probably in the Applications folder.
Right click it and choose Show Package Contents.
Open Contents, then open MacOS.
iTunesHelper is in there.
Message was edited by: Timothy Westman-Barth