This year, like every year, one of the most common questions iMore's being asked is -- how many betas will the be before iOS 6 becomes available to the general public?
At WWDC 2012, when Apple announced iOS 6 and released the first beta, they also announced that iOS 6 would ship sometime this fall. (Presumably and traditionally a couple of days before the next generation iPhone 5 ships. That gives us a window roughly spanning from September to November. We likely won't find out the exact iOS 6 release date until the iPhone 5 event, but that also hasn't been announced yet, and typically won't be until the last minute.
So all we can really do at this point is look at history for clues, and go through the mental exercise extrapolating past behavior to try and predict future behavior.
Update: Will Hains has posted a dynamic, graphical representation of the number of days between iOS beta releases. Check it out at willhains.com.
Here's the full beta schedule from last year's iOS 5 release:
Here's the beta schedule to date for this year's iOS 6 release:
Here's how that looks on a calendar:
If Apple sticks closely to the every-two-weeks pattern from here on out, and the same release schedule as last year, there's enough time to squeeze in 8 betas. If any of the betas take longer than 2 weeks, or last for extended periods like the final beta last year, then we could see as few as 6.
So, if past behavior is any indicator of future behavior, we can expect 6 to 8 betas total for iOS 6, with a Gold Master (GM seed) at the iPhone 5 event in early October, and a final release in early/mid October when the iPhone 5 ships.
Given Apple's penchant for secrecy and lack of predictability at times, the only real schedule for iOS betas is to expect them when you see them.