Firefox have rreleased the latest screenshots to its major update which would be the Mozilla Firefox 4.0. It would primarily focus on windows users , the look and feel distictly matches that of Windows Vista or Windows7 users running Microsoft’s Aero interface.
The mock-ups show three few different versions: One with tabs below the navigation toolbar, another with tabs above and another with a “combo stop/refresh/go button”.

One can expect more customization[Which designers believe were lesser in previous versions] to be available in the update and more useful updates such  as full title bar visibility in the tabs .
As Stephen Shankland at C|Net’s Webware blog notes, the design with the tabs on top definitely look familiar, with more than a passing resemblance like Google’s Chrome.
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