P3 is the standard for digital cinema projection in theaters, and for certain photo professionals and film and video experts, this is potentially a big deal. For photo hobbyists, you're unlikely to be able to appreciate the difference, as very little consumer-grade equipment is going to give you files that can take advantage of the wider P3 color gamut (some dSLR cameras, however, can). However, in side-by-side testing using some sample images, the effect was subtle but impressive, with richer reds and greens, and Apple's photo apps as well as third-party programs such as Photoshop, all support color far beyond standard sRBG.