I know it's stupid to chase every rumor, but the latest one today from iLounge makes a lot of sense to me. Especially because they imply that Apple will change the aspect ratio (and pixel resolution, something along the lines of 1280 x 720).
I'm not saying this is a great move, but it makes sense. Especially because the rumor goes on to say that the width would not increase, just the height. As I said before, I think Apple decreased the width with respect to the iPhone 4 as a step forward. Making it wider again doesn't make much sense.
The rumor finishes by talking about a newer dock connector. This is somewhat troubling to people who purchased docks to use with the iPhone's/iPod touches.
Who the f really knows, but it's fun to speculate.