If you have a Sony NEX or Fujifilm X-mount camera then check out Gordon's "reviews in progress" of the new Touit lenses from Carl Zeiss. The 12mm f/2.8 is here
and 32mm f/1.8 is here
From what I can gather both lenses use a retro-focus design, something that might be of particular interest to those with the NEX-7 which provides something of a challenge near the corners for wide-angle lenses that use a symmetrical design. Maybe the 12mm is the dream wide-angle lens for that camera? It'll be interesting to see as testing continues...