It only took Mozilla 5 Betas and 2 1/2 months to fully respond to the backlash of the new add-ons bar introduced in Firefox 4 Beta 7. Back when I installed Firefox 4 Beta 9, I discovered the lack of usability with the new add-ons bar which was introduced in Firefox 4 Beta 7. Mainly, it no longer displayed the status of the page loading and more importantly, it did not show link targets (address when hovering over a link). Instead link targets were shown (and not very clearly) up in the address bar.
Improvements did start coming with the Beta 11 release in early February. Page loading status was added as an over-lay above the add-ons bar. Now, with the recent Beta 12 release at the end of February 2011 link targets are now also displayed as an over-lay above the add-on bar.