There are claims that Leopard already has support for Bluray movies (commercial ones) through the use of DVD Player and the Sony BWU-100A Recorder in an external Firewire enclosure.
These claims have yet to be substantiated and in most cases can be dismissed as they would either be coming from people who are pirating and hacking software or are in violation of their Non-Disclosure Agreements.
Remember, these are people who on many occasions have given us elaborate mock up iPods, tablets and other imaginary products with wild and outrageous claims.