Just a quick question.

I'm not familiar with MacBooks, but your question was interesting. Chatter in the MacOSX forums (http://macosx.com/forums/hardware-peripherals/277655-how-get-stuck-cd-dvd-out-macbook.html) indicates the disc may get stuck on the top of the slot as the disc comes out on some models. Inserting a thin card on the top of the slot can help guide the disc down and out.