If you haven't already started using (read: beta testing) Firefox 3, I highly recommend that you check it out. Apparently there are lots of changes from Firefox 2, but here are the ones that have made a major difference for me (enough of a difference that I even suffered through the early betas [*shudder*]):
1) the new URL bar - remember in old days when you used to start typing a URL sequentially and the URL bar would auto-complete it for you? Yeah, well that was nice back in 2007, but FF3 has created the new generation of auto-complete. You can start typing *any words* (or parts of words) from a URL that you have already visited and the prescient FF3 will figure out what you mean. Here's an example:
Let's say you've recently visited my post on Epicurious and can't remember the URL:
You know that it had "blog" and "epicurious" in the URL. So, you type "blog epicurious" into the URL bar and FF3 shows you the correct URL. Awesome!
2) It's fast. Not explanation necessary.
FF3 is currently in RC2, so most of the major bugs should be worked out. If you don't feel like using anything but the "stable build," the formal release of FF3 should be pretty soon. You will love it.