http://www.spreadfirefox.com/en-US/worldrecord/

Basically, Firefox 3.0 is coming out. I've been using the beta for a few months now and it's much improved over the 2.x releases.
It's faster and more lightweight. It's tailored to be faster with many Big sites.
Gmail positively flies along with it.
There are a few issues with many addons not working for it yet, but that should be sorted by release or soon after, i think.

If you follow the above link and pledge (giving your email addres) and they'll email you on the day Firefox is released (this month) with download links for it. The idea being that as many people as possible download it on release day to set the record for most software downloads in 24 hours.