The OS itself handles 99% of what users use their optical drive for. 3rd party/external readers and burners will still work, just not with 3rd party apps or MAS apps.

I'm not trying to brand this as a great thing or anything, but it does seem very likely to me. If you develop an app that requires access to the optical drive, I wouldn't hold your breath for MAS support. The way I see it going down is Apple grants companies like Roxio temporary exceptions until they kill off products like Toast once and for all, and then Mac OS X drops support for optical media just like they did with floppies.