There's a rumor going around that iOS 4.0.1 and/or iOS 4.1 have been delayed by Apple in order to combat potential Jailbreaks.
Firstly, Apple is secretive to the point that no one outside the iOS team and top brass likely knows when they're planning on releasing any iOS update, ever. There are plenty of bugs like the antenna reception, the proximity sensor, 3G speeds, the camera roll, etc. that need to be fixed before it can even be scheduled. Everyone else is guessing or passing on heresy, including Apple Store employees, carrier reps, and internet aficionados.
Secondly, Apple is almost as cyclical as they are secretive, so while we don't know the precise day iOS 4.0.1 or iOS 4.1 will be released, we know when iOS x.0.1 and iOS x.1 have been released in the past.
Neither iOS 1.0 nor 2.0 nor 3.0 were bug-free and while it's easy to forget, users were clamoring for fixes almost as much in years past as they are now. That said, iOS (iPhone) 3.0.1 was released July 31, 2009. 2.0.1 was August 4, 2008. 1.0.1 was was July 31, 2007.
So if Apple sticks to end of July/beginning of August, we have several weeks to go before we'll see iOS 4.0.1, or see if anything has been "delays".
iOS 4.1 is even further out. Heck, iOS 4.x hasn't even gone into beta for iPad yet!
Apple typically releases those x.1.0 updates to coincide with new iPod touch generations at the iTunes/iPod Special Music Events held in the fall, and then follows with an x.1.1 update for iPhone shortly thereafter. iOS (iPhone) 3.1.0 was released on September 9, 2009. iOS 2.1.0 was September 9, 2008 and 2.1.1 was September 12. 1.1.0 was September 14, 2007 and 1.1.1 was September 27.
So if Apple again sticks to the September schedule it will be a few months before Steve Jobs takes the stage to show off new iPods and whatever new features come with the next minor iOS bump.
As of now we're taking any reports of iOS delays with huge, Cupertino-sized grains of salt. Sure, if a Jailbreak is released that will highlight a major security exploit in iOS and Apple will have to patch it. That's been true in the past and will be true in the future. It's why the Jailbreakers often wait until after iOS releases to go public with their exploits.
Other than that, there's been no date other than "a few weeks" that could be delayed, and the usual schedule is far out enough that it's take a while before even internal delays can be guessed at.
Now, with that out of the way, we're free to speculate wildly about what just might make it into a fall iOS 4.1/4.1.1 update -- but we'll save that for weekend post...