That spanish villa motorcycle ad is the craziest computer rendered pic I've seen so far I think. There's very few things there that I would spot outright as signs that the pic is computer generated, the stone driveway looks a little flat perhaps and the shadow of the potted plant against the wall is too sharp. Other than that it looks very very realistic. Not many would be able to tell the pic is fake if they didn't know beforehand it's a rendering.
The catcher's mitt, the lettuce and the doggie also look crazy good.