Since you have to take off the cover to upgrade the ram on the macbooks you have pretty easy access to the optical drive. Once blu-ray burners/players are thin enough to fit on the macbooks do you think we'll be able to replace it ourselves?
possibly, but it would still have to be the right voltage, have the right drivers for it, and have OSX support blu ray (which is might be as early as the next update)
Another thing to think about is the cost of BL too. The part of superdrive costs about $150+, so I imagine BL is more expensive. I might have to go with PS3 (a nice excuse to buy!).