I'd say the experience is quite easy, especially when using browserid.org/verify for verification.
My biggest criticism is the lack of a concretely defined spec for how the Verified Email Protocol works, if one wanted to implement it directly, rather than relying on browserid.org.
Based on the code in the repository, the protocol seems relatively straightforward. But, as it currently stands, it'd be difficult to implement it based on the paper spec alone.
Anyway, nice work on BrowserID. I'm excited to see where its headed.
Ah, yes, silly title. I meant to add "toolbar" at the end of that title, which makes it make a lot more sense. Will fix that shortly on the blog.
As for the viewing area, There is one point where the menu goes off to the left side, so I couldn't crop it further (I wanted to keep the window in the center of the video, as well).
Anyway, let us know what you all think of the API we are proposing! We really want to see this take off.
(I'm the author of the blog post/video btw, in case that wasnt clear!)
Let us (the BrowserID team) know if you have any feedback on the experience.