Updated Update: This story originally said that Mozilla had released the first Firefox 4 beta. But the beta has not been officially released. Last week, Mozilla told us the first beta would arrive "within days."
Mozilla has released a candidate build for the first Firefox 4 beta.
Developer builds of the open source outfit's next-generation browser carried the old Firefox 3.7 name, but the new beta candidate builds have officially adopted the Firefox 4 handle. Mozilla intends to roll out updated betas every few weeks before the browser's official launch, slated for November.
But these features will be gradually rolled into beta builds.
It appears the beta candidate is little different from the last developer build, Firefox 3.7a6-pre. This includes several interface tweaks, including a new Firefox button that aggregates your most frequently used menu items; the ability to drag and drop items on the toolbar; and tabs that appear at the top of the browser by default, Chrome- and Opera-style.