The design of the optical drive remains unchanged. The optical drive in this particular Xbox 360 E is the Lite-On DG-16D5S.
Microsoft claims that the Xbox 360 E is "quieter than ever." How much of that quiet has to do with the fans is unknown seeing as how the fan is identical to the fan found in the Xbox 360 S.
The fan is labeled as X858313-008; its lovely cowling is labeled F94, or X857295, in fine print.