Rated 5 out of 5 stars
Very nice! I'm not totally tweaked about the usage reporting stuff, but they are up front about it, and it appears to be 'harmless', so no worries for now...
The only thing I'd like to see is support for 'non-active' functionality - meaning, require a right-click on selected text - which would also disable the 'hover' functionality too. Adding this optional behavior *should* make it possible to support Thunderbird too (which I would *really* like to see).
Bottom line: great extension!