The touch panel described in the patent would generate an electrical field which would be used to sense when your finger is hovering above the display by measuring the capacitance fluctuations in the electrical field. The trick with a system like this is to keep a high degree of accuracy when there are other objects (like your other fingers) disturbing the field. The patent describes a couple possible ways to deal with this, including an option where hover gestures would be turned off on a section of the screen where your palm or other fingers are touching the display.
Motion, but those systems use a combination of cameras and infrared light to track your movements. We've seen products like Senseg, which uses an electrical field for kinetic feedback, which would make you feel different textures from your touchscreen display, but this one is definitely different. Apple filed this patent back in 2010, and it was just granted today. The patent is incredibly detailed, and you can jump over to the AppleInsider source if you're interested in the more technical explanation.The idea sounds pretty interesting. We've seen gesture control systems before like Samsung's Air Gestures, Microsoft's Kinect, and Leap
*Update* A reader pointed out that we did forget something: the Sony Xperia Sola's "floating touch" feature, which does seem to be doing the same thing, in the same way as Apple's patent. Both use the same self capacitance sensor to detect hover events and mutual capacitance sensors for normal touch events. Of course, Sony's tech was first shown off last year, Apple filed the patent in 2010, and it is unknown if/when Sony ever filed a patent on its technology in the U.S.
The other patent granted to Apple today is for an embedded heart rate monitor is one that doesn't really seem like something that deserves a patent, because it describes a system where a heart rate monitor is embedded into the metallic conductive portions of a device. This type of system can be found in plenty of different devices right now, but Apple's twist is that it would be used to detect electrical signals so small that they could be used to identify a user. This is a really interesting implementation, but one that can be found in other devices as well, so it's a matter of if Apple's patent, filed in 2009, came first.