With all the rumors that have been circulating in recent months about Apple’s possible iTV, there have been all sorts of questions about the device. How big will it be? What features will it have? How much will it cost? When can we buy one? One question, however, has plagued the device all along: can an iTV do to the HDTV market what the iPhone and iPad did for the smartphone and tablet markets? More to the point, can the iTV do in in a way that the Apple TV can’t?

Many have felt that the answer is probably no. The HDTV market is too well-established for Apple to come along and revolutionize it the way they have other markets. The smartphone had almost no appeal to the consumer market until Apple came along and showed consumers the iPad. The tablet market was hardly worthy of the name until the iPad. That’s not the case with the TV market. The TV market has been targeted mainly at consumers since the beginning, and there are countless good TVs available for customers to choose from – many already having the advanced “smart TV” features of the kind you find in an Apple TV (e.g., Netflix).

What, then, is Apple to do? While it’s possible they could release an HDTV that would revolutionize the TV market in the same way the iPad and iPhone revolutionized their markets, it doesn’t seem terribly likely. And yet all the signs point to Apple having some sort of TV-like device in the works. Not least among these signs is Steve Jobs’s statement to his biographer, Walter Isaacson, that TV was one of the last things he worked on at Apple, and that he had finally “cracked it.” That makes it sound like Apple does plan to revolutionize the market. So what’s the solution?

James McQuivey of Forrester Research has an idea about what Apple might do instead of an iTV. He thinks that instead of just building a TV, Apple plans to build – or should build – “the world’s first non-TV TV.” This device, which he calls the “iHub,” would be, as the name suggests, the hub of a family’s daily life. Here’s McQuivey’s description below:

Instead of selling a replacement for the TV you just bought, Apple should convince millions of Apple fans that they need a new screen in their lives. Call it the iHub, a 32-inch screen with touch, gesture, voice, and iPad control that can be hung on the wall wherever the family congregates for planning, talking, or eating — in more and more US homes, that room is the dining room or eat-in kitchen. By pushing developers to create apps that serve as the hub of family life — complete with shared calendars, photo and video viewers, and FaceTime for chatting with grandma — this non-TV TV could take off, ultimately positioning Apple to replace your 60-inch set once it’s ready to retire.

Whether the kind of device McQuivey is talking about really is what Apple is working on is impossible to know at this point, but his idea certainly has merit. As he points out, the life cycle of a TV is generally far longer than that of most other consumer electronics. Most of us don’t buy new TVs nearly as often as we buy new phones, tablets, or computers. As McQuivey points out, Apple isn’t going to make its customary zillions of dollars by trying to convince people to replace a product they may have spent a thousand dollars on just a few months ago. A device like McQuivey’s iHub would provide Apple with a foot in the door of the TV market while also convincing people that they need another device that’s far more than just a TV – and that’s uniquely Apple. When Tim Cook unveiled the new iPad in March he talked a lot about the post-PC world and the iPad’s place in it. A device like the iHub would go a long way toward both hastening the arrival of the post-PC world, and introducing the post-TV world along with it.