So Blogger realized the error of their ways and fixed the problem where you needed a Blogger ID to link within a comment. On VDog’s site there’s a great email from Blogger admitting to the fact they eliminated the URL field prematurely.
One thing of note – if you self-host your own site like I do, you need to obtain a OpenID. Great instructions here on getting a OpenID for a self-hosted WordPress site or any other self-hosted site.