This is true. Not only am I in the phone book, so anyone who knows my name and approximate place of abode can find my address and phone number, but for various reasons my address and phone number have appeared on Usenet (and hence on google groups). My date of birth has also appeared in several places. And given my address and name anyone can look up things like my DoB anyway from official sources. And other things banks treat as 'security' questions like my mother's maiden name. OK, my credit card details haven't, but as you say making any transaction with them could have had the details given or sold to anyone. So as far as LJ is concerned, I don't see that they can do any worse with my personal information.

On the other hand, I'm not going to make it easy for criminals by posting them on my LJ posts and profile, just as I don't leave my front door open when I go away for a week. If they want to defraud me they can at least do some work to find the information...