Similar previews have appeared around the 'net (our friends at Engadget have published their own review), and while Apple claims that images and descriptions in the post are still confidential, The Register disagrees, saying that many features of Snow Leopard were seen and known way before this week.
So. Will Apple be angry? Will The Register be locked out of any future events (actually, we can identify with that one, given our metaliveblogging chops here on TUAW)? Will they care? It does seem a bit strange that Apple has targeted them with a takedown -- we doubt, as The Register suspects, that Walt Mossberg will be getting any takedown notices. Then again, maybe Apple was just trying (or their lawyers were just aiming for some extra legal fees), and they won't bother enforcing what seems like a shaky case anyway.
Most likely Apple will pass. We'll probably hear them exclaim, however, though it may be less staunch: Merry updates to all, and to all a good launch!