Next week, when Apple holds its annual special music event, we probably won't get iOS 4 for iPad. We'll almost certainly see that new iPod touch 4 with Retina Display and FaceTime and an announcement about iOS 4.1 for iPhone general availability, probably for later that week. But if iOS 4.1 was going to be the grand unification, universal binary edition for iPad, it would have been released for developers over two months ago when it was released for iPhone and iPod touch.

Sure, Steve Jobs could simply announce iOS 4.1 and release it for iPad right then and there on stage -- if any company could be accused of being inoculated against the cries and concerns of developers, it's Apple. But even Apple has a pattern of releasing betas for significant OS updates. Simply put, to do otherwise could lead to broken apps and unhappy customers and that's not in anyone's best interests.

Chad and others have argued that iOS 3.2 for iPad is already pretty close to iOS 4, and that's a fair point. However, iOS 4 contained a large number of new API, including multitasking, and developers are going to want time to test against them, and against anything unforeseen that might cause problems for their apps between iOS 3.2 and iOS 4.

The most likely scenario I can come up with is that Steve Jobs announces a beta version of iOS 4.2 for iPad next week and after several betas, releases it to the public in October or November -- a timeframe that's been rumored for a while now.

I mentioned this yesterday on Twitter and several really smart mobile folks think I'm wrong. Some really smart mobile folks who are also developers seemed to think they'd need somewhere around 4 weeks of beta lead time, at least.

There's nothing I'd love more than iOS 4.1 for iPad next week, but while Apple is secretive they're also fairly good at sticking to patterns. And the pattern here is several beta releases before a general release.