Please ignore this if you're building anything for regular people.

OpenID is confusing and painful to the end user, and you'll lose a significant fraction of your potential userbase if you don't let them sign up for an account with their familiar username/password.

There's only one OpenID site that's valuable enough to me to jump through the constant hoops required to setup & maintain an OpenID account, and that's StackOverflow. So unless your thing is obviously going to be more valuable to me than SO, you won't get my signup if you force me to use OpenID.

I like OpenID but my fear is that only tech people use/know what OpenID is. I will think about this. Thanks for your feedback! :)

It's okay that you're not using OpenID. It's a pain in the ass to use. It's one of the reasons I don't like using StackOverflow, for instance.

I agree, even as a super technology addict, I find OpenID to be super annoying, and I even have a friend who use to be the OpenID advocate. Heaven forbid I should tell him that though :)