Hmmmm...let's see...
Hagrid's hut is pretty much done.
Flying Unicorn/Flight of the Hippogriff hasn't really been touched.
Dragons hasn't been touched.
Site work for Hogsmeade is coming along, but there hasn't been any actual construction.
The show builing for the Kuka arm ride is built, and the ride is being slowly installed.
The Hogwarts castle facade for the top of the show building is due to start work soon, if not already just begun.
Estimated opening date...my guess...next summer. At best. Unless they decide to do a phased opening, and let guests into the areas that get finished first.