Why do so many media related jobs use mac?

A number of industry standard media tools got their introduction on the Mac. In 1985, it was Aldus Pagemaker which brought about the whole Desktop Publishing concept. Adobe Illustrator followed in 1987, and then Photoshop in 1990. The Macintosh's graphically oriented nature made it a natural fit with these products, and they were all introduced as Mac-exclusive apps.

So why does everyone use Macs now? Well, that's because that is what everybody else uses. Odds are in your media project you are going to be working with partners that already on the Mac Platform, so you might as well use a Mac too. Its a self-sustaining phenomenon.

If all of this DTP business had gotten its start in Windows, it would probably be a different story today.

Apple knows that the Mac has a significant presence in the publishing/media business. Mac OS X today features a number of core system features that reflect this. ColorSync. Display PDF. Resolution Independence. Core Image. Core Animation. OpenGL (not so good for gaming, but a must for high-end rendering). A robust image compositing engine. Audio Units. There is a lot of technology that the average user rarely runs into but for the professional makes their lives that much easier.

Jam it back in, in the dark.