If you're worried that she will keep a copy:

    "People are worried that I will take your
     passwords, but in reality I won’t be able
     to remember them ... I don’t store them on
     any computer anywhere.  As far as I know
     there is only one copy of your password."

    As she reminds customers on her website:

    "The passwords are sent by US Postal Mail
     which cannot be opened by the government
     without a search warrant."

Interesting article, interesting idea, it always comes back to: just who do you choose to trust.