Graet,
I'm very sorry for what happened, You run the great pool and I hope that your pool would survive for the sake of the bitcoin network.
Nevertheless: What do you use to store passwords inside the database. Is there a possibility that password hashes were compromised during the last break in? What algorithm do you use to store password hashes inside the database: SHA1, SHA256, do you use salt? I'm asking because many users are using the same password and username with many pools and online accounts.
Thank you