Panasonic has succeeded in producing the first 9.5 mm blu-ray burner for laptop.
With such thickness (or should I say thinness) we can expect the MacBook Pro to be equipped with such devices in time.
This drive is able to burn BD-R 2x in single layer, double layer in 1x. Naturally it can also burn CDs and DVDs.
Current model uses a tray, nevertheless Panasonic will probably offer slot-in drives shortly to suit Apple laptops (price unknown).