Hum, this could be interesting when all is said and done: "Supernova Fail: Giant Dying Star Collapses Straight into Black Hole" -
space.com/… - "It appears the path to becoming a black hole is more complex than astronomers thought. Rather than exploding into a supernova before collapsing into a black hole, as expected, one giant star skipped the pyrotechnics and went straight to the collapse. "