It means they had a security issue that let someone steal their database.
The DB shows they have lots of bitcoins and money available, but that doesn't mean anything because if they were hacked in the manner they described the DB would still show them as having bitcoins that they don't actually have.
This means the information presented matches multiple scenarios including the bitcoins were stolen by Gox, the bitcoins were stolen by hackers and the exchange is still operational and fully funded. It rules out a hack that involved someone removing coins in a way that updated the bitcoin balance in the DB (such as password theft) but there was never any speculation that such an attack had occurred so that isn't helpful.
The DB shows they have lots of bitcoins and money available, but that doesn't mean anything because if they were hacked in the manner they described the DB would still show them as having bitcoins that they don't actually have.
This means the information presented matches multiple scenarios including the bitcoins were stolen by Gox, the bitcoins were stolen by hackers and the exchange is still operational and fully funded. It rules out a hack that involved someone removing coins in a way that updated the bitcoin balance in the DB (such as password theft) but there was never any speculation that such an attack had occurred so that isn't helpful.