It's nice, but... there are several usability flaws.

For one, I can't change the search focus by clicking in a frame. I find this particularly annoying when I'm checking the javadocs and I want to search for a particular method or class in a given classes' docs.

For another, I'd like it to auto-hide when I click on a link in the page; if I'm leaving the page,I'm obviously done with the search. If I need a new search, I can just hot-key the bar back up.

Speaking of which, what's the hot-key to hide the bar? I'd like to have one. Search bar keyboard shortcuts in general seem to be non-obvious.

All that said, firefox is, of course, a rockin' browser. I just want it to be even better :-). Gotta teach myself xul one of these days...