On Thursday, invitations were sent to select members of the press for a special event at the Flint Center for the Performing Arts in Cupertino, California on Sept. 9. With the tagline "Wish we could say more," what's Apple hinting at?

As we previously reported, the rumors of an Apple event to unveil new products to the public on Sept. 9 were proven correct when Apple sent out invitations marking "9.9.2014" as the official date. 

It's no secret that the new OS X "Yosemite" and iOS 8 operating systems are set to launch this fall, but with a cryptic tagline "Wish we could say more," what else could Apple have up its sleeve?

Apple iPhone 6: Larger Screen and Sapphire Glass

First thing's first: With all the buildup and leaks about a new iPhone 6, you can almost guarantee Apple will have at least one new smartphone to show off come September. And it's likely that, just like last year, there will be more than one variant of the new iPhone to choose from.

Previous reports indicate the iPhone 6 could come with the usual 4.7-inch screen and also, in a first for Apple, a larger size, which could have a screen up to 5.5 inches. Another report sourced to The Wall Street Journal indicates there could be two versions of each of those iPhone 6's -- one less expensive and one with the highly scratch- and crack-resistant Sapphire glass.

iWatch: A Good Possibility, According to a Good Source

The same day the Apple invites went out for the Sept. 9 event, tech watchers Re/Code (formerly AllThingsD, which had a great track record) reported that the Cupertino company was planning "to unveil a new wearable alongside the two next-generation iPhones."

While not naming the iWatch specifically, this seems to indicate the long-rumored device could be unveiled in September. The report went on to detail Apple's purported plans to intertwine the iWatch with Apple's HealthKit fitness and health-tracking platform, along with HomeKit, which is Apple's software foray into the connected "smart home."

Long-running rumors could support the unveiling of an iWatch soon -- and the fact that Google recently launched its own multi-wearable platform this summer would certainly spur Apple to compete -- but we'll still have to consider the iWatch this September as a "good possibility."

"Wish We Could Say More"

Companies like Apple and Google love to tease the public -- and information-hungry tech journalists -- with ambiguous clues about what's about to be unveiled when they send out invitations. For example, last September's Apple event invites featured colorful circles and the tagline, "This should brighten everyone's day," weeks before Apple unveiled the candy colored iPhone 5c. And the clear circles in the invite turned out to be the iPhone 5s's "home" button. For another example, the first iPad mini was preceded by the tagline "We've got a little more to show you."

Not every Apple invite is as tantalizing as those, but generally if they include an indistinct message such as "Wish we could say more," the company is usually hinting at something.

Prognosticating based on the Apple invite of course carries a big risk of failure, but it's fun to try anyway. (It's too bad Apple didn't say something like "Watch what happens" or "It's time for something new.")

Here are two of my guesses:

Siri -- "Wish we could say more" could refer to the spoken interaction of Apple's Siri personal assistant software. As we reported, Wired recently got a sneak peak at "Viv," a revolutionary next-generation Siri that a small group within Apple was working on, but there were no indications the software was anywhere close to ready for primetime. However, an updated Siri-heavy Apple TV or iWatch with integration into the "smart home" could make sense.

iWatch -- As we saw, not clues are in the text. And if you look closely at the drop shadow of the "leaf" part of the Apple logo, you'll notice it's unlike the design and shading of any official Apple logos, even the soon-to-die-out skeuomorphic Apple logos in OS X Mavericks.

(Photos : Screenshot: Apple OS X Mavericks, Twitter: @NickBilton )

What does that mean? Possibly nothing. But knowing Apple, the company wouldn't just put a drop shadow on their invite logo on accident, and the resulting shadow effect vaguely resembles hands on a clock, which could hint that the iWatch is real and soon to be unveiled.

Unveil Date = Release Date -- This one isn't tied to the invite, but Apple happens to be offering a "back to school sale" with $100 gift cards for Mac purchases and $50 gift cards for iPhone and iPad purchases. When does the offer end? You guessed it: September 9. Perhaps this time, every new device -- new Macs, iPhones, and iPads -- will be available for purchase at Apple Stores across the country as soon as they're unveiled on stage in Cupertino.

Are we grasping at straws? Probably, but it's hard not to theorize when Apple offers tantalizing clues like these (do you think Apple sincerely wishes it could say more before the event?).

What are your theories? Let us know in the comments section below!

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