I doubt that the pro machines and the cinema displays will go to a glossy-only configuration. Like others have said, Apple would want to give the option to those users whether or not they want something that displays colors in a more traditional sense like a matte screen or one that alters the colors like a glossy screen.
Personally, I hate the glossy screens and it is my sole reason why my next computer will not be a MacBook but rather a MacBook Pro.