Personally, I'm doubtful that Microsoft would do this mainly because it doesn't really move them to a position where they will be able to sell more units and gain greater market share ...
If I was in charge of Microsoft, I would focus on moving all components of the XBox 360 towards the 45nm or 32nm process, and find a cheap alternative for a hard-drive (potentially an flash memory card encased in their hard-drive enclosure), in order to produce a "Slimline" XBox 360 that could be sold at a very competitive rate (potentially $200).
Soon enough the XBox 360 will be a 3 year old console and it really needs to be in a position where it is at a mass market price with the features people see as acceptable; moving towards Blu-Ray only works against this goal.
