I don't see why a ton of people see this as a far away idea... If it does exist, here is my thoughts as to why it does. One simple thing, fast app switching (much like the 3/4 finger side-swipes on lion, but with one finger). It's coming with the iOS 5 on the iPad. Using so many fingers on a phone screen (even if it is a 4" screen) is not very comfortable or simple. Swiping across a button is. It would still be a clickable button (much like the magic trackpad) so accidental button clicks would be as rare as it is now and very rarely would you accidentally swipe your finger across it if you held it sideways... I actually have no qualms with this if it happens like I said and other than it looking unfamiliar, the design, I think, is still quite nice. My 2¢ Agree? Disagree? Why or why not?