I want to post this because it is such awesomesauce. Yes, I'm patting myself on the back. I (as far as I know) have the world's first WordPress installation that takes advantage of the "siteName" and "siteLogo" feature of Mozilla Persona. I think I am the first because I just got done writing the implementation.
Marcel Bokhorst's great WordPress Plugin is 3 days shy of a year old. Marcel had the plugin ready 24 hours after BrowserID's initial release and has been keeping it up to date ever since. I highly recommend using it on your own WordPress installation.
Because I wanted to contribute back to Marcel, I have created a patch to support siteName, siteLogo, as well as update the old browserid.org URLs to login.persona.org. The patch has already been sent to Marcel, hopefully it finds its way into a version soon.
You can try the patch out here by posting a comment, you'll see my name and ugly mug inside of the Persona dialog.
Until Marcel reviews and merges(?), you can try the updated BrowserID Plugin on your site. You'll have to get some patch-foo ready, I'm intentionally making this hard to use until Marcel's full review. Make sure to back up your version of the BrowserID plugin before applying. And finally, if you wonder why siteLogo isn't working for you, it's probably because your site is not being served up using SSL.
A text copy of the patch can be downloaded at https://shanetomlinson.com/static/browseridwordpresssitename.diff