In case you don't know what OpenID is, here is a link to the official site. Basically it's a universal login service so that people don't need to create new accounts for different website, but can instead log in with an existing username and password.
I would like to use it on my site... I think.
Do sites with OpenID actually gain more members? I mean, if I could "register" by only entering my username and password on every new site, I would definitely join pretty much every site I liked the layout of 😵 (But that's just me.)
No, thats not it at all. You know how you can login to Youtube with a Gmail (or google) username and password? It's the same idea. Actually I think that's OpenID at work. It would allow anyone with one to just log in and post, without actually registering.
What if someone got your password? They could screw you over on every forum, bill pay service, website, or whatever else you are joined up with using this.
I prefer making individual accounts for things myself.
I haven't used them but have heard good things about them. Anything that makes it easier for users to join your forum can be helpful. Many forums have visitors who don't register because 1) they don't want the hassle of registering or 2) they don't see the registration link.