Will Microsoft be incorporating BluRay drives into the Xbox 360? It's entirely possible that MS will offer BluRay support in the new console, despite having backed HD DVD to quite a degree. The industry is still split very 50/50 and it makes sense to try and get support for as much as you can.

“At present time, considering such part [external optical drive], Microsoft selects HD DVD. But since it is unknown whether HD DVD and Blu-ray wins [the format battler], we took the form, external drive, which allows us to change in future situations,” said Peter Moore, head of the Microsoft interactive entertainment division in an interview with ITmedia web-site.
These are interesting developments. Both HD DVD and BluRay are set to make market appearances this year, and Microsoft has stated that addon drives for the 360 will be available this year as well, perhaps as soon as this summer.