Now, they even mentioned this in the article, but imagine this. You buy an Imac. It comes with a wireless keyboard and wireless magic mouse. The keyboard and mouse DO NOT NEED BATTERIES they simply just work when they are on the same desk as the Imac. Right now users are having to swap batteries in their wireless accessories, with this technology (when more mature) they simply wouldn't, they would NEVER have to think about batteries in these accessories again.
The other benefit, you have an Imac at home. You SET YOUR IPHONE ON YOUR DESK and it charges. Magically!