Firefox 12 will feature long-awaited New Tab Page and Home Tab

After a long gestation period, it now appears that Firefox 12 — which moves to the Aurora channel at the end of the month — will feature the long-awaited New Tab Page and Home Tab. The new tab page is very like Chrome’s feature of the same name. The home tab builds off the new tab page popularized by Chrome and Opera, but then throws in ton of Firefox-unique functionality.
At the moment, the new tab page really just shows you a 3-by-3 grid of your most-visited websites (pictured above). You can pin a tile, or — if Firefox has turned up a particularly embarrassing site — you can hide a tile (in which case the next-most-popular site appears). You can also drag and drop the tiles to rearrange them. For now, that’s the extent of the new tab page’s functionality.
The Firefox home tab is a lot more exciting. Basically there are two phases: The first phase will add “launchers” at the bottom — one-click links to your downloads, settings, apps, and so on (pictured right). Phase two is a complete reworking of the home page paradigm, weaving in favorite apps, recent websites, and even instant messaging (pictured below). Phase one is expected to roll out with Firefox 12, but at the time of writing the code still hasn’t been committed.
In other news, Firefox 12 will also bring URL autocompletion to the Firefox address (née awesome) bar, ala Chrome. Firefox 12 is also meant to be the release that heralds deeper web app integration, much in the same way that Chrome features apps and favorite sites on its new tab page. This is meant to be built into Firefox’s home tab, but again as that hasn’t yet landed, this might not make it into Firefox 12.

Update 01/27/2012 @ 12:15 ET: In a perfect example of why you shouldn’t rely on Nightly builds, the New Tab Page has actually been removed from the latest Nightly. If you want to try it out, you’ll either have to wait until it’s put back in (hopefully tonight or tomorrow), or use the UX Nightly build.
Update 01/29/2012 @ 7:15 ET: It now looks like at least the Home Tab, and possibly the New Tab Page will not arrive until Firefox 13; they just weren’t ready for Firefox 12. (If you’re using the stable channel, Fx13 should around the end of May.)
If you want to try out the new tab page, download the Firefox Nightly. You then need to visit about:config and set the value of browser.newtabpage.enabled to true (double click it). You then need to set the value of browser.newtab.url to about:newtab (again, double click it and type it in). Finalize the changes by restarting your browser.