Yeah, I don't know why they're gone. I don't think they'll ever comeback, but I don't see why automotive companies wouldn't try. I mean, there are a good chunk of people who like them. I love the streamlined look when down, and the creative "coming alive" feel as they open up. I know you posted in the thread I'm about to link to, but this is for others in the thread to see.
Cars with interesting Headlights, Import Atlanta Thread
(a bunch of cool headlights in that thread, some pics, mostly videos of really cool opening mechancisms)