Google toolbar is out with a new version 5 in beta. While I find myself using Firefox more often than before everyday, I’m still on Internet Explorer the majority of the time, perhaps due to force of habit, or the fact that some sites display better on IE. I have refused to upgrade IE 7 however. Version 6 runs just fine for me.
Ironically, what keeps IE a viable browser for me is Google toolbar. There are plenty of useful and time-saving utilities in the toolbar from quick access to Google search to spell checking, to auto-filling forms.
The new toolbar is similar to the last version, but there is one feature that I stumbled on by accident that really made this version worth the upgrade. The toolbar hooks itself into the search function (Edit-Find…Ctrl+F) of IE and displays a Firefox-style search bar at the bottom of the page with similar functionality as that of Firefox. The web page document is searched and the first match is highlighted as the search term is being typed. It's a giant improvement over IE's stodgy pop-up search box.
I'm not sure if the Beta version is available for Firefox yet, but if you want to try the toolbar out on IE, pick it up here: http://toolbar.google.com/T5/