The Washington Post had a very unique map that shows two possible arcs along which the last none ping was received. One arc is north of, and the other is south of, Malaysia. The article does not say why there are two arcs but I assume it is because the possible positions along the arcs are derived from the time the engine pings took to get to the single satellite. If two satellites had received the ping then we would know the position of the last ping.
Since the northern of the arcs is well over land, somewhere from what looks like one corner of La0s, over China and ending in a bit Kazahkstan and given that the last public radar position is on the west side of Malaysia, it seems unlikely that the plane could have crossed the coast lines of and crossed a county or two without being seen on radar or the Mark I eyeball.
That leaves the southern arc which is in a very remote area of the world and only two countries that would have radar coverage. Australia and Indonesia. It looks like the closest the plane could have gotten to Australia was a bit over 700 miles. Because the Aussie coastline recedes away from the possible last position arc, the plan was mostly likely much farther from Australia than 700 miles. Does Australia have radar coverage in that part of the country that can see out a 1,000 miles? I kinda doubt it.
The most likely location of the plane is on the southern arc south of Indonesia and along the coast of Australia. But much closer to Australia than Indonesia since the northern most part of the southern arc is near Jakarta. Surely Jakarta radar would have picked up the plane at the position and it would have been difficult for the plane to have gotten to that area without being seen if flying at lower altitude.
If it was terrorism per say and the pilot was ticked off at the Chinese governments treatment of Moslims, why not crash the plane in the capital of China? It would have been easy to do since that was the destination of the plane.
The mostly likely answer is that the plane is sitting on the bottom of the Indian ocean after one of the flight crew went bonkers. Just like what happened to the Egyptian plane a few years ago.
Later,
Dan