Snow Leopard will end an era that few have noticed. Ever since real color was introduced on the Mac the “gamma” of Mac displays has been set to 1.8. You can think of gamma as a kind of brightness, and Microsoft chose a different gamma for PC’s: 2.2. This 2.2 value was more like the NTSC television most of us watched. Apple stuck with the 1.8 value, baked into Quicktime and later Quartz, right on up to today. But I note that the Snow Leopard preview states that from Mac OS X 10.6 on, the default gamma setting for Macs will match that of PC’s: 2.2. Non-color-managed images will seem a bit darker, but then they have always seemed darker to PC users, and there are more of them!