It’s no secret that Mozilla is working on a fairly major facelift for the next major version of Firefox. We’ve already seen some early concepts for Linux and Windows and there’s even an easy-to-install Strata 4 theme (called Strata40) for current versions of Firefox.

On his personal blog Chromatic Pixel, Mozilla contributor Stephen Horlander has shared some more iterations of the Windows version. Early in the post, Horlander admits that Mozilla’s undivided attention has shifted toward implementing a new theme for v4.0. Firefox 3.7 likely won’t see a UI update.

One thing which is clearly getting a lot of attention is the application button. It’s been tested in at least the five positions you can see in the bottom of the header image (and likely several others). Mozilla is taking a cue from Microsoft here, looking at the single-button menus in Windows 7 apps like Wordpad, Paint, and just about anything else with the Ribbon UI.

Personally, I’m a fan of the options on the top and bottom right – they seem like an efficient use of space and a good fit for widescreen monitors.

What do you think of Strata 4.0 so far? Where would you like to see the application bar placed? Does it even matter? This is Firefox, after all, so v4 is going to be as customizable as other versions have been.

[via IThinkDiff]