The Anti Glare films disrupt the characteristics of the Retina display. They were fine when the resolutions were lower, but as companies like Samsung and Apple push for higher resolutions, it is getting harder and harder for the film manufacturers to produce a Matte/Anti Glare film that does't degrade image quality.
It will be interesting to see what Power Support comes out with. I love their products, and use their Anti Glare on my iPhone 4S, but it does diminish the display a bit.