At this point, the timeline of events greatly suggests that Mt. Gox's initial announcement of withdrawal freezing was the point at which they were officially dead. If the insolvency document is true, over 700,000 bitcoin was stolen, due to a bug in their cold storage (likely, it wasn't truly cold, but automated filling a hot wallet).

In the last two weeks, they were probably attempting to see if there was any way to reverse or mitigate the damage. This is the point at which they have determined that there is no 'out.' They have no where near the amount of bitcoin required to even service withdrawals.

Edit: http://support.mtgox.com/ now shows that their Zendesk account has been terminated (a new account can be registered at that address).