I can't help thinking this is a bit shortsighted, unless it's purely a marketing stunt by the spreadfirefox people. Are they really affiliated with mozilla?

Unless mozilla have hired an Exabit/s connection to the Internet for the day, they could be setting records for the world's slowest download!

I've been using FF3 (it was in beta with Ubuntu 8) for a few weeks now, and I quite like it. It doesn't feel like a different browser from FF2, but it does seem like the right tool for safely and easily browsing the Web.