From the Reuters article above:
The chief crash investigator, Mardjono Siswosuwarno, says the aircraft's wing flaps failed to extend for landing and that might have been caused by the high speed.
"This could be a contributing factor, but what is more important is that the plane's speed was higher than normal. Why? We don't know yet," Mr Siswosuwarno said, from the National Transport Safety Commission, told Reuters.
The questions now become, what would be the options for the pilots (assuming they were aware of the flap problem) as they were coming in without proper flap config?
Also what could cause such a malfunction?