Some stuff is endorsed by the studios. Some stuff isn't. We have no way of knowing what is, and what isn't unless they tell us. If they don't want it up there, they can have it taken down. We might be doing Fox legal a favor by showing them what's on the open web. I have a real strong feeling a lot of streamed video is allowed to stay up by the studios at the present time as viral marketing.
As far as I know, at the present time, if it's on the open web rather than a torrent, or filesharing program it's legal.