What exactly are OpenID usability issues? I personaly prefer to use OpenID where it is available, yet I don't use any login provider but a php script on my own website.
I suspect that until things like a TondioPlug become useful for a lot of people, (if they ever do) asking people to be their own provider will be a lost cause.
IMHO, one of the things they do correctly is that the user doesn't have to remember an OpenID url in most cases, just click on the logo for which of your likely ID providers (Google, Facebook, Yahoo, etc.) that you want to use. What could possibly be easier or friendlier for the end user?
The problem is that StackOverflow is also about the only example of OpenID done right, or done at all...
Yes, there are a few others. But at least in my internet usage I hardly ever run into one. I can't remember having used my OpenID for any site other than SO in the past couple years.
* Tripit.com only supports Google, Google Apps, and Facebook, but it's very end-user friendly to use any of those three.
* Catch.com, like Tripit, supports Google and Facebook OpenID logins.
* mindmeister.com supports Google, Google Apps, or a generic OpenID login.
* springnote.com supports a number of openID providers including generic OpenID. This one is actually an even better example than StackOverflow of an end-user friendly OpenID login/signup page.
Those are just ones I pulled from my Google account settings page. I'm sure there are other good examples out there.