I dunno folks, this sure does sound like a bomb to me:

A Qantas flight to Melbourne made an emergency landing today after a large hole appeared near the cargo door.

The plane made the landing in Manila about 1:20pm after the cabin depressurised due to what sources have described as a "massive" hole in the fuselage.
...
Qantas this afternoon was still trying to establish how a large hole came to appear in the fuselage outside the baggage compartment.

It definitely wasn't a hatch failure... you can still see that, firmly shut, a few feet in front of the hole. This picture shows an intact one at roughly the same angle. Looks like a big chunk of faring came away. It also looks like this happened near the same point the bomb that took down Flight 103 detonated.

I don't like this. I don't like it one bit. Weirdly, there are probably a bunch of Boeing guys right now secretly hoping it was a bomb, because otherwise there'll be several hundred 747s grounded immediately. If it's wrong in the structure, it'll be wrong on a whole bunch of them.