Yes, he is insane. (h/t Think Progress)
Update: As Think Progress notes, CBS has ordered YouTube to take down the video clip. It can still be viewed (at the moment at least) here. I really recommend watching this while it is still available, as it has to be seen to be believed. I had thought O'Reilly's eruption at Geraldo Rivera was bad, but this is far beyond even that. He really does appear to need some serious therapy or something ... In case this goes down again I'll sum it:
O'Reilly is reading from a teleprompter when he begins having difficulty reading it. At this point he starts getting angry - very angry. After stating that there are no words on it for him to read (by point he is shouting) he ask shouts "what does that mean, play us out?" and has to be told it means to end the show. So he begins another take, botches it and appears to snort a deep breath of pure rage. He tries another take and at then transforms into a raving lunatic screaming that he can't do it, he'll do it live - "FUCK IT - DO IT LIVE!!!!", he'll write it himself and do it live. "THIS FUCKING THING SUCKS!!!!!"
Next, he manages to pull himself together for approximately 20 seconds to actually do the take. Now the sound cuts out, but you can see O'Reilly rip off his coat and storm off while still screaming at someone. It is just bizzarre how furious he becomes over something so trivial.
I have to wonder how often O'Reilly explodes like this off screen. There is no way in hell I would work for or with anyone screaming like that. I'm surprised his heart hasn't exploded yet.
Update II: Crooks and Liars has it, too.