If you’ve noticed that your comments don’t show up right away after you post them, it’s most likely because they’re waiting for me to approve them. Automatic approval is linked to the e-mail address you enter on the comment form (which won’t be displayed anywhere on the site). If I’ve approved a comment with that e-mail address, all future comments from the same address will be auto-approved.
As I mentioned, the e-mail address will never be displayed on the site (to anyone but me), but it will be stored in the mySQL database. If the database or my WordPress account is ever hacked, your e-mail address will be visible to the hacker.
That said, I don’t care if you use a real e-mail address when you post here, so if you want to use a bogus one for commenting in my silly blog, go right ahead. Entering an e-mail address is beneficial in two ways: First, instant gratification for you. All future comments will be auto-approved. Second, less work for me. I get a dozen or so spam comments held for approval every day, and I’d hate to miss a valid comment when I’m running through and deleting ads for bondage gear or on-line poker.
Actually, I’ve been toying with the idea of adding a captcha plugin (worst acronym ever) that would allow on-the-fly approval by requiring commentors to enter an alphanumeric string displayed as a graphic. That would probably make the whole e-mail business moot. What do you think?