Oh no, this is definitely official, see The Brothers Brick entry here. I think the set is fantastically awesome, the dark tan 'brick' bricks look really good mixed in among the sand green. It also comes with a great selection of these, which is quite nice. I love the interior too!
I made a similar looking house myself for a halloween display at home, but this really has a lot of nice features and design elements. I was thinking it would look great on "the other side" of the Cafe Corner series of sets, like on a hill just past all the Creator homes. It would even make a good Tom Riddle house for the Harry Potter line.
There is no life I know to compare with pure imagination. Living there, you'll be free if you truly wish to be. -Willy Wonka, 1971-
The price is a little scary (heh heh... you know, because it's haunted), but it is a neat set. Lots of sand green and good "castly" parts too. If I did buy one, I'd probably sell the figs (other than the ghosts) to try to offset the price a little bit. The fold-out attic ladder is a really nice touch.