It's not that simple. From wackypedia: "The sRGB color space standard used with most cameras, PCs, and printers does not use a simple power-law nonlinearity as above, but a decoding gamma value near 2.2 over much of its range." Both the sRGB and Adobe gamuts are huge. Very few, if any monitors are capable of displaying them in their entirety. Even the aforementioned Eizos "only" reproduce 98% of Adobe RGB, and that is a pretty impressive achievement. It is perfectly possible to make an image look good under gamma 1.8 or 2.2, but in general most images will look better when viewed on a properly calibrated monitor tuned to 1.8. OSX does now default to gamma 2.2, but it is possible switch the it back to 1.8 and that's just what most photographers do. As I said before, gamma 1.8 is essential when doing image preparation for printing, especially if doing one's own color separation from RGB to CMYK.