Hyperwords.net

I'm interested in what people think of this browser approach and Firefox plugin, Hyperwords, now in version 5.0

There's both a user-driven version, demonstrated above, as well as a client-side version that turns every word on a website into a hotlink. The former seems like a great way to be carrying a little toolset with your cursor everywhere you go. The latter seems like a great way to build a giant hypertext community around a book Finnegans Wake or even the Torah.

Is this a dimensional leap for web browsing, just another plug-in, or somewhere in-between?