We don't enforce very much in the way of password policy. You must have a password, that is it must not be empty, apart from that limitation are you are free to pick whatever you want. We believe that our users know what is a reasonably strong password for whatever they are going to plan on this site.
As with all you passwords, don't ever resuse a password to something very important like your bank account or your email login. We store the password in a one way ecrypted form using an industry standard algorithm. It is reasonably secure even if someone would be able to hack our server and we are of course never going to have anyone get access to the password willingly and we are never going to look at it ourselves. We are one of the good guys... However, that does the bad guys also say, so think before you choose your password, on this site and every other site where you register.