Firefox 3.7's Windows 7 shell features continue taking shape
Jump List support is much more complete now, and it's also highly customizable. The about:config page now includes preferences for each group on the list -- tasks, recent pages, and frequently visited pages. You're also able to specify the maximum number of items you want displayed in each list. To locate the Windows 7 preferences, just type taskbar into the config filter box.
Aero Peek and Superbar thumbnails, unfortunately, still seem to be experiencing the spinning wheel problem. No image appears, and the Aero Peek preview shows only an empty gray window. Personally, I'd rather just be able to click back to my Firefox window anyway -- and not have to hover and choose a tab first.
If you'd like to take the Firefox 3.7 pre-alpha for a spin, download it from the Mozilla FTP.