A recent patent filing was discovered at the USPTO which shows a MacBook wirelessly charging an iPhone, this can be seen in the sketch below which was including with the filing.
As we can see there are charge points either side of the trackpad on this MacBook, so you would be able to charge two devices at once wirelessly. The text below was also taken from the patent filing.
An electronic device and methods for inductively charging an electronic device using another external electronic device. The electronic device may include an enclosure, a battery positioned within the enclosure, and an inductive coil coupled to the battery. The inductive coil may have two or more operational modes, including a power receiving operational mode for wirelessly receiving power and a power transmitting operational mode for wirelessly transmitting power. The electronic device may also have a controller coupled to the inductive coil for selecting one of the operational modes.
It is not clear as yet on when Apple may introduce this new wireless charging feature to their range of MacBook’s, as soon as we get some more details we will let you guys know.