Mozilla developers blog posted about the Firefox 4 release date info and feature overview, "We've worked tremendously hard on Firefox 4, and it's time to ship it. I'm seeing the same burst of excitement and activity that we've seen in the endgame of every release.
Over the past several days, component leads have again reduced their blockers by identifying hard blockers and those we can live without. We've around 160 hard blockers remaining, and historically it has taken us six weeks to reach RC once we have 100 blockers left. We must press hard now."