I hate being skeptical but if apple gave him a beta copy or whatever wouldn't they have a contract saying he cant leak videos?
I realise 10.6 is pretty much all under the hood, but since seeing no other previews of 10.6 on YouTube, Metacafe or any other site, I didn't believe you could get a copy of it right now. Obviously I was wrong...
And in the description of the video is says it shows the new Safari working; Is it just me, or does it look and do the exact same as normal Safari??