Firefox 4.0 beta 1 released, get it while it's hot!
If you've been using the bleeding-edge 3.7 alpha builds, you won't notice much difference -- but if you've been holding off, waiting for things to firm up a little, now's the time to hop on!
The most significant change (other than OMG SHINY WINDOWS 7 AERO UI!!!1) is the inclusion of a built-in Feedback tool. Right there, in the top right corner, you have immediate access to two buttons -- happy and sad. (Check out the happy feedback submission page, it's rather cute.) The Feedback feature also includes Mozilla's Test Pilot, the add-on that lets you take part in anonymous usage studies (like the one used in the Firefox heat map). You can opt out of the feedback system at any time, of course.
Anyway, rather than repeating every new feature in 4.0 beta 1, just check the Mozilla blog instead. I'm now going to put Firefox 4.0 through its paces and see if it benchmarks faster than 3.7!