I think that the whole blu ray vs zune thing stems from the PS3 vs 360 fight, in the end Blu ray will become the new standard and zune will be relegated to obvlivion once Apple releases a new Ipod with fast streaming.
Zune as a platform has already failed versus the Ipod Touch and Iphone and no ammount of technological advances will reposition it let alone make it a standard. The tech heads will probably go crazy over it for a while but the general consumers will rather wait for Apple to do the same, or expect the DSi or PSP to do so accordingly.
True, digital downloads are the future but it's still too far away to kill physical media, and there is still wariness that all the media you can buy today might be useless tomorrow with the changes in streaming, the restrictions of playback systems and the server side storage that might become so huge that will start to delete some stuff and make our "buy" useless.
Digital downloads might replace blockbuster since I see it more as a rental system than as a way to buy movies while blu ray will replace DVDs.