2 valid arguments:
1. Content creators need to proof their content, preferably with instant feedback on the machine they are creating it on.
Why can't they just proof their content from the HDD? The only extra thing they would learn from doing it from an actual Blu-ray disc is tell them is the factory that pressed it did so correctly.
2. The computer division, indeed, the entire platform, is in danger of disappearing under a sea of neglect by refusal to maintain its cutting edge technology, superior to all other competitors.
But if the expensive computer hardware can't do it as well as the cheap standalone player, if anything that should
sour the user experience with the computer, not enhance it. And Apple is all about a positive user experience, even if they have to deny users things that, while desirable, might sour said experience if they did not execute properly.
On the portable side, you'd need a MacBook Pro 17" to view 1080p content natively, but you'd still be listening to it in stereo over the speakers or headphones. So you get nice video (on a really small screen) and junk audio.
And is anyone really going to use a 27" iMac or a Mac Pro with a 24"/27"/30" LCD as their primary Blu-ray viewing device? And run HD audio from it? Or are they really going to run a mini-Display Port to HDMI cable from their iMac / Mac Pro in one room to the television in another?
So the real machine people want Blu-ray on is the Mac Mini because they want to use it as an all-in-one HTPC source. And yet the Mac Mini may not be able to handle a Blu-ray disc without dropping frames. So what is the answer? More powerful GPU? More powerful CPU? Some custom DSPs to handle the HD audio streams? People are already rioting on this forum over the current price - now add $250 for the BR player and the extra hardware to make it perform as well as a $250 standalone Blu-ray player.
I'm sorry, but the answer to me seem to be to just buy the standalone player. Many of them can stream content from Macs/PCs and they can access Netflix and Pandora and Amazon and Blockbuster and other sources. They have hardware optimized to play back 1080p video with no dropped frames and output an HD audio signal to a dedicated receiver/decoder connected to 6/7/8 speakers.