6 = current beta, will become release in 1-2 weeks 7 = current alpha (Aurora), will become beta when beta gets released 8 = current nightly, will become Aurora

6 = current beta, will become release in 1-2 weeks 7 = current alpha (Aurora), will become beta when beta gets released 8 = current nightly, will become Aurora when...you get the point So basically Firefox 6, 7 and 8 have already "come out" and you can use them if you're willing to run beta or alpha software. (In my experience, Aurora is already very stable, much more so than normal alpha software) The versions advance in a 6 weeks cycle. I'm guessing the above has been explained about 1000 times when Firefox 5 came out soon after 4, anyway.