Quick edit: First video was deleted by the user, so I added a new first video from RT, which is a collection of different videos from different people of the event. Incredible footage.
For some reason, I have not seen it on American "news" TV shows.
More videos and a very limited explanation:
Explosions in Chelyabinsk; Meteor Suspected
More videos linked, from a reddit post:
Amazing footage from multiple sources.
Also, this is the building impacted showing a big hole and another building with broken windows from the shock of the impact:
Last video; note how it gets very bright and then very dark.
I have no idea why it would get so dark - light, yes, a comet streaking across the sky and impacting, but why the darkness?
Was it just an effect on the lens from the extreme brightness?