Purely speculation here:
As Gizmodo points out, the new final Cut Pro Studio allows direct burning to BluRay Disc. Problem is, Apple doesn’t sell any Blu-Ray hardware…yet. Steve Jobs famously called Blu-Ray "a bag of hurt" because of all of the licensing restrictions, etc. that went along with putting BluRay into Macs.
You could always, of course, buy a Blu-Ray external disk and use Roxio Toast Software($63-73)+BluRay Plugin to burn, export and watch BluRay discs. However, this is the first time Apple’s own software has referenced Blu-Ray (besides that iTunes/Gracenote mention that made everyone pee their pants a little).
Apple being Apple, they will likely offer a built-in hardware solution, if only in high end Pro machines during the next iteration. Their industrial/pro customers don’t want to source third party hardware that isn’t supported under the same warranties that Apple provides. That is unless "someone" thinks they are just too painful to see in Macs.