Before the end of the year, we will be upgrading the software that runs this site to a new version. One of the requirements for it is that when you login, you do not enter your username. Instead you will enter your email address and your password. This means you should make sure you know what email address is associated with your account before the upgrade eventually happens. Your password is not changed, your username that displays here on the site is not changed. The only thing that is changing is that the login form will ask you to enter your email address and password in order to gain access here.
