Mozilla contributor Stephen Horlander is still hard at work, sharing his ideas for a revamped Windows 7 theme for Firefox 4.0.
According to Horlander, the expected Firefox facelift is now solely expected in Firefox 4, and not gradually through Firefox 3.7 and Firefox 4.0.
In this revision, the Application button (marked #1 on the mockup above) has been reworked to incorporate the new Windows 7 single button menus, already present in Paint and Wordpad on Windows 7.
Work has also been done on the toolbar and location bar.
More mockups and information can be found on Horlanders blog post.
Current Firefox users can download the Strata40 Firefox Theme, which gives the browser a similar appearance.