Up to this point, we’ve been assuming that Apple would unveil the iPad mini alongside the new iPhone at its September 12 event. Why? Because the often-accurate Rene Ritchie said so, and his report, at least the date, has been confirmed by a number of news outlets.

But today, John Gruber of Daring Fireball contests the information, making a pretty strong case for why Apple would hold two separate events. He opines that since the iPhone is Apple’s single most important product, it’s unlikely that it would share the spotlight…

“I’m thinking it makes more sense for Apple to hold two events. First, an iPhone event, focused solely on the new iPhone and iOS 6. Then, the iPhone ships nine days later, and there’s another wave of iPhone-focused attention as the reviews come out. Then, in the first or second week of October, Apple holds its traditional “music event”, exactly along the lines of the events at which they’ve been debuting new iPods for the last decade.”

This actually makes a lot of sense when you think about it. Last year’s iPhone 4S event ran just shy of 100 minutes  long covering iOS 5, and an iterative iPhone upgrade. Now imagine how much longer it would be considering what’s on the menu for this year.

The new iPhone, with its larger display and LTE-compatibility, will be one of the largest upgrades in the handset’s history. And on top of that, Apple is also said to have new iPod touches, nanos, and a new iPad ready to start shipping this fall. How long can one event last?

Gruber’s theory of two events is pretty smart: talk about the iPhone and iOS 6 at one event, and then hold a second “iTunes” event to talk about the smaller iPad, the new iPods, and possibly the long-rumored iTunes 11 update.

Of course, this by itself is speculation. But The Loop’s well-connected Jim Dalrymple pointed to the story this afternoon, commenting “Oh that Gruber is a smart fellow.” And given Dalrymple’s track record on Apple intel, this adds some serious weight to the argument.

My only problem with this? Apple’s never held two significant media events this close together — within weeks of each other. But it certainly makes a lot more sense for it to spread these product announcements out, rather than trying to cram them all into one keynote. And I wouldn’t be the least bit surprised if the iPad mini, among other products, didn’t turn up on September 12.

What do you think?