All facetiousness aside, I think this is going to be popular provided they don't screw up on apps. I would like a fully curated store from Microsoft but they should offer the ability to allow any Windows program to run.
Personally, I prefer using microSD's. Mechanical drives that spin kill batteries fast. My tablet will allow me to watch non-stop movies for about 15 hours before the batteries die on it from microSD's Using a mechanical hard drive via USB, more like 7-8 hours. Not sure about a DVD drvie, but it should do the same or less.
My work laptop will rock out about 4 hours doing normal work, a DVD will cut it down to less than 2.5.
I just use DVD Catalyst to rip my movies to mp4 format and I can get lots of them in a nice little 64 GB microSD card.