<-- (typical Firefox 3 user... you can tell by her chest... like the front of her shirt, I mean...)
I've been using the betas and release candidates of Firefox 3 for a while and I haven't gone back to 2.x since. Even though I don't use a lot of the new features, the browsing experience simply feels faster and the browser supposedly uses less memory, especially when having many tabs open. Typically I have at least 3-4 tabs open when I'm not really surfing the web. I keep Gmail and a couple of news type blogs open all the time. When I am looking things up and stuff, I can easily pass 10 tabs open, so more memory efficiency is a very welcome thing.
Go get Firefox here! They are trying to set a record for the most software downloads in one day, so grab it today to take part in the record attempt.