I have just deleted my password, accidentally (which is not a crisis, but it shouldn't really happen).
I logged in to tweak my page subscriptions, did so, and clicked 'save preferences' - unfortunately, the password boxes are cleared when you arrive at the preferences page and if you don't fill them in again then the new password (which is blank) gets saved. I'm sure I'm not the first one to notice this - I'm just writing here because I've not yet found anywhere where this inconvenience is documented.
-- KarlMW