That is incorrect information regarding the glossy screens. Provided you are in a dark environment during calibration, the glossy screens calibrated fine. My Gretag MacBeth i1 (spectrophotometer) works well with LCD's whether glossy or matte. However, it works best if you do not follow the normal instruction of placing the sensor directly on the screen. Instead, I mount the sensor about 10 inches away from the screen with its sense axis PERPENDICULAR to the screen surface. Pulling it back restricts the sensor to seeing that is exiting the screen perpendicularly and improves the calibration accuracy. Otherwise, off angle light also affects the sensor and you end up with a less accurate calibration. The room must be otherwise dark. BTW, you can't restrict the viewing angle of the Spyder (tri-stimulus sensor) in this manner.
The out of box LCD calibration for every single of the 12 macBooks and macBook Pro's I currently utilize were unacceptably tinted for critical viewing. Each one arrives from Apple with a different color characteristic. Even ones of the same model don't necessarily color match each other out of the box. The unit to unit variability of displays makes it impossible for a manufacturer to deliver a truly calibrated display. Many are glossy screens, but calibration to d65 gamma 2.4 (to simulate CRT response), grayscales are neutral and much more consistent from machine to machine. Each panel needs to be profiled individually and re-profiled periodically to deliver accurate color representation. It takes about 6 minutes per display so the process isn't practical for the manufacturer to do on each unit. Even if Apple did calibrate the displays individually, they drift over time. I recalibrate my main screens once per month. More critical users may need to do it more often.
Very few people have had the opportunity to enjoy a calibrate image. Until recently, the cost of an accurate measuring instrument was been prohibitive. Now, there isn't much of a cost barrier. An X-Rite EYE-ONE Display LT Monitor Calibrator streets about $150. Just make sure you get one with a multiple workstation license. Once you know what a calibrated display looks like, your eyes won't tolerate a non-calibrated display. A calibration device makes a huge difference and is far more accurate than the subjective guess by eye method included with OSX.