Last I've heard is that after 14 weeks of searching, not a single piece of debris from the plane has been found. Now, Australian authorities are changing the search area yet again.

I think this one is going to turn into an Amilia Earhart, where what actually happened isn't going to be known for decades. At this point, we don't even know for certain that the plane crashed.

The only evidence of foul play so far is that the hard drive in the flight simulator that the pilot had at home shows that he was practicing landing on an island. And, that's the full extent of the evidence against him.