[snogglethorpe]

That's the thing that first came to mind when I saw the pics of those doors opening... sure they look cool, and probably work ok if you're outside away from anything, but seems like there are plenty of situations in which they just wouldn't have the space to open enough to allow exiting (at least without crawling on the ground).

Examples might be a small garage or a parking space hemmed in by other vehicles.

Sliding doors take almost no extra space to open fully, and even normal swing doors can be used when partially open (the exact degree of course depends on how skinny you are...).

[dangrossman]

The video shows it opening when parked so closely to two vehicles that a person can barely squeeze through, and when parked in a garage with a low ceiling. One of the cars they parked it next to is a minivan with sliding doors, which you couldn't get into when open, while you could get into the X. As Elon puts it, paraphrasing, "this is the best aperture possible".

[tcskeptic]

Did you watch the unveiling event? It is a dual hinged door and can do some pretty trick stuff with ultrasonic sensors to alter hinge and lift angles to open in pretty tight spots.