Read More.For the users who want the cutting edge, Firefox 10 should be the interesting release. It's already spent six weeks in the Nightly channel, where active development happens.With Firefox 8 now available to everyone in the stable channel, all of the other Firefox versions are graduating as well. Firefox 9 is moving from Aurora to the Beta channel, Firefox 10 is moving from the Nightly channel to Aurora.
In this time, the features that will eventually make it into Firefox 10 when it lands in the stable channel, early next year, have been fleshed out.
As soon as Firefox 10 ends up in the Aurora channel, new features, at least big ones, will not be added.