The openid-selector client, if you are talking about how to use StackOverflow, has no server-side hooks at all, just like the HtmlHelper in DNOA, since the openid selector does not make AJAX callbacks to the server. The DNOA selector control uses AJAX to provide users with the ability to automatically log in, automatically detect when an identifier is entered, etc.
So yes, the openid selector (SO style) is much simpler and works great with DNOA.
And yes, DNOA's built-in AJAX selector loads slower. This is what I (or the volunteer) still need to work on acceleration.
source share