Even if you get the HD Movie in You cannot watch it in high Def you need a high Def screen to watch high def movies.you will get the same quality as normal movies. I think that the 17" high Resolution Screen supports High Def movies but i stand corrected if i am wrong.
Seriously - some people need to learn about HD before spraffing about it!
There is two forms of HD, 1280x720 (720P) and 1920x1080 (1080P/I). All Apple laptops are capable of displaying 720P.
If you watch a 1080P movie on a screen that has a resolution lower than required, the movie will be
downscaled to fit the screen. As all Apple laptops can do 720P, the movie will effectively be downscaled to the quality of 720P.
High Definition came about because we have huge TV's, yet awful broadcast resolution to go with them. But, that doesn't mean that HD can look staggering on a laptop. It will look better on your laptop than on your TV (if you were at the same viewing distance) because the laptop has more pixels per inch.
Watching HD on a laptop will look staggering. You will be able to sit with it on your lap and experience extremely high detail, compared to the awful resolution of standard definition.
To answer how people will get Blu-Ray Disc movies onto their Mac, there is Blu-Ray drives for Mac's out there but they are pretty expensive. Rumours say that Apple was to include a Blu-Ray drive in the new MacBook Pro's, but Sony had troubles with the slot-loading drive including all aimed capabilities.