When you create an eshop and online gaming network you can be cheap on many things but one, security. Sony knew this very well but you cant always win. That's what happened in Sony's case. Sometimes it's an employees fault, other times is an undiscovered security hole. Whoever it is to blame Sony got hit big time and it cannot recover even after almost a month. Lets see some of the major events in chronological order.
April 17 to 19: This is the period when PSN security was breached. Sony notices strange activity and finally shuts PSN down.
April 20: A security firm is hired to investigate, Sony makes its first public announcement.
April 21: A second security team is hired to offer assistance.
April 23: The security teams confirms that the attacks were sophisticated and coordinated perfectly.
April 26: Sony informs the public that the attackers may have access to personal data like credit card numbers.
May 1: Sony hosts a press conference to inform the public thoroughly. It announces possible PSN recovery by the end of the week.
May 3: Sony claims the hackers behind the attack were members of the well known group anonymous. Found evidence in a file left behind by hackers. The anonymous group deny any involvement.
May 6: Sony announces that the restoration will be delayed.
May 10: Sony announces there is no firm date for the restoration.
May 15: Partial restoration of PSN for basic services and available only in North America, Europe, Middle East, Australia and New Zealand. Read more
here.
UPDATE
There are no news till today that could shed some light as to whats going on with the network.
For news and everything keep an eye on the blog.