Seriously, they can track phone calls from all over the world, yet they can't find a plane?
It ain't quite as simple as that :L

I think it's gone down in the pacific ocean west of Australia, as is the common international opinion (else they wouldn't all be searching there), and unfortunately I believe they may never find it. The ocean is deep; may sound like I'm channelling Captain Obvious, but it is, and I think it will be a long time before it's finally discovered, if ever.

The real question is why it was flying in that direction, and I then agree that somebody probably knows something about why it happened. Unlikely to be terrorism; terrorists have a tendency to make a song and dance about their actions, else it wouldn't have the same effect. Personal reasons might be more likely, but I'm not going to speculate on what they might be...