It's only a patent, so don't get too excited (though I have to admit, I'm already pretty excited).
"On March 19, 2010, Patently Apple presented a special report titled 'Apple Files a Mysterious Projector Patent' which provided an overview of pico projectors coming to Apple's media players, future MacBooks and a possible new product which would combine a pico projector with Apple's AirPort Extreme. Others saw it as a natural for Apple TV and all in all, pico projectors will be for work and play.
In today's patent, Apple's R&D team all but confirms that pico projectors are indeed coming to future MacBooks and details a sweeping overview of the system in a patent published yesterday. The patent also generally confirms rumors of HDMI coming to Macs – being that pico projector based MacBooks list this as a possible feature..." (Read more).