Firefox 5 and hiding the navigation bar

I got prompted to update my Firefox 4 to Firefox 5 beta last week. New features include better standards support, speed improvements, better integration with Linux desktops, in-browser software channel selection and support for CSS animations. The final version of FF5 is expected to ship on June 21th.
Firefox 5 will probably not include one of the much discussed hidden features in Chrome 13; the possibility to hide the navigation bar, but Mozilla indeed is experimenting with that as well. I’ve got Mozillalabs Prospector’s Simplify Firefox add-on installed on my netbook and in that 1024X600 context the extra screen real estate is a huge advantage. On the other hand, on my 1440X900 work laptop screen I don’t need (or want) those measly extra pixels. Maybe hiding the navigation bar should be an option which is by default off on normal-sized screens and is automatically turned on for screens with a netbook-like resolution?