Well why do they make high def TVs? And thoes are watched from a distance and show amazing sharpness.
It would work great on an iMac, videos, text, photos etc
Watching my iPod Touch from a distance of 10" is identical to watching my current 27" iMac from 11 feet. But my iMac is a 'retina' display from a distance of 2 feet, at which distance the screen is much bigger than the Touch.
Now on to TV's, to get Retina on a 60" HD TV you need to watch from a distance of 8 feet. More than 8 feet and you don't get any extra benefit. So to get the biggest image filling your field of vision, you want to know what is the closest you can view a screen while still maintaining it's retina qualities.
Viewing a 60" HD TV from a distance of 11 feet is identical to viewing my 27" imac from a distance of 2 feet with regards to image size.
So the answer to your question is that many more people can watch the screen from 11 feet than can watch my iMac from 2 feet.
If you move 3 feet closer to the 60" HD TV to it's retina limit, then you'll get a bigger image than on the iMac, but not much bigger.