I didn't expect this one.
If you haven't already read up on the review craziness that began yesterday...well, you can find it all right here. The long and short of it was that RotR reviewed a preview copy, one they played back in August, and ended up breaking their review embargo. Oops.
Victor Lucas, one of said reviewers, actually posted an apology and an explanation as to what happened. He begins "We screwed up", and explains what happened. Props to them for the apology, though I do wonder if they're only doing it to save face with Warner Bros.
Further, they promise to do a re-review once the review embargo ends, which they reveal is September 14th, a day before release.
[Thanks, Anon commenter!]