"We have something you really have to see. And touch," says Apple's invitation to a March 7 event in San Francisco that will almost certainly serve as the public debut of the iPad 3. (See the invitation below.) The company has a habit of dropping subtle (or not-so-subtle) hints in its invitations to big product launches, and this time appears to be no different. The "coy" graphic shows a user's finger pointing to the tablet's Calendar icon, which features a number seven. What does it all mean? Here, three theories:

1. The iPad 3 might not have a home button
If the device in the invitation were a normal iPad, there "should be a home button visible," says Chris Davies at Slashgear. But it's not there. Maybe Apple is finally scrapping the physical home key and making its devices cleaner and purely gesture-based, or using touch technology in the bezel (the black surface area around the screen) in lieu of a button. Unless they simply turned the iPad upside down in the picture, say Jesus Diaz and Adrian Covert at Gizmodo. But why would Apple do that?

2. The "retina" display is for real
The tablet screen pictured in the invitation boasts much sharper resolution than the iPad 2, says Eric Zeman at InformationWeek, meaning a high-definition "retina" display is almost certainly on its way to store shelves. Just look at it: The text is sharper, and the icon detail more pronounced. And the invitation reads "…something you really need to see." It makes complete sense that the iPad 3 will be all about its "dazzling display." Yeah, says John Gruber at Daring Fireball. The line in the invitation even "sounds like something Steve Jobs would say."

3. The screen might be feelable
With any luck, says Harry McCracken at TIME, the new iPad will boast "at least one interesting twist which nobody's predicted just yet." And the dangling second sentence could clue us in. "Touch" may mean that the iPad 3 will come with "some sort of haptic feedback," technology that allows users to feel textures on the device's screen, says Lex Friedman and Dan Moren at Macworld. (Read more about the technology here.) Typing on the iPad is, for the most part, an unsatisfying experience. Imagine if you were able to feel the physical sensation of a "depressed" key as if you were typing on a real keyboard. You might get the chance to try it out in a matter of days.