Have experimented with Chrome and like it - particularly the amount of screen real-estate it renders - but am running into a number of sites without Chrome support, so it's back to Firefox, plus plugins to give a Chrome-like experience.
The essential Firefox plugins for me are:
Adblock Plus - obviously :-)
Tab Utils Lite - Adds tab duplication
Easy DragToGo - opens tabs by dragging links
Pimpoflage - Hides top bars and status bars (also the menu bar can be hidden from standard Firefox toolbar customisation and displayed with the Alt key)
Mini-UI is a simple alternative which hides / reveals using rhe Ctrl key.
LastPass - Password manager that syncs passwords across browsers
Other invaluable add-ons:
Gmail manager - Shows number of messages for multiple gmail accounts (check
here for latest fixes)
Forecastfox weather - Brilliant weather icons in the status bar
Delicious Bookmarks - Social bookmarking at its best
QuickProxy - Easily turn on/off proxy settings
Kaboodle - Sharing shopping lists
IBM add-ons:
Foxear - IBM internal delicious equivalent
IBM CCK - Internal search engines and password management