That's right, Firefox 4.0 here on an internet near you...
As far as i can tell its the same old, faster, safer, stronger that all of the software updates normally are. But it does include some nice new features too, such as the App Tab.
After releasing a final Beta a few days back, we've got the real thing, so I downloaded and installed it, giving it a run for its money. It does seem to be up to standard with the new IE9 I posted about not too long ago.
Check it out for yourself, here.
Look out for our head to head comparison between IE9 and Firefox 4.0.