If you play EQ2, even if your account is expired, go to your account ASAP
and change your password. You can get directly to the account login page at https://auth.station.sony.com/login
If you had an active account, you have 45 days added to it. That's one free month plus a day for each day the service was down. (It looks to me like it was 12, but that's their math.) http://www.soe.com/welcomeback
Sony claims that your credit card number was safe. Personally, I'm planning to have my credit card reissued and will change my accounts to a different email address so that I can recognize fake account spam more easily.
It's unfortunate that it will be harder to recruit EQ2 addicts using the AAF program, but for the sake of my friends' sanity, I'm glad they're back.