I only use Firefox except for a few work related pages where I am mostly forced to use IE8. Just installed FF4 after reading this post - I like it so far (all 5 minutes of it!). It does seem quicker and I already noticed improvements in the way it handles add-ons. That by the way is what I like alot about Firefox and is why I use it - the customisation that can be done to tailor it to your needs with the add-ons.

Dan
On-Wall M5HP LCR, QS8 & EP500 in 7.1