Of course Apple is already working on a new iPad mini with a higher resolution screen, and a full-sized iPad that will be thinner. Apple is always working on better, next generation versions of their devices. However, if you want to scratch "reportedly said so by sources in the supply-chain" off your rumor list, now you can. At least, according to Digitimes:
The sources have yet to specify whether the device will use Apple's Retina Display technology to enhanced resolution, but market observers said it is highly likely based on the development of past Apple products such as the iPhone and 9.7-inch iPad series.
Meanwhile, the sources also said that Apple will restructure the lighting of the next-generation 9.7-inch iPad from two LED light bars to one in order to decrease the device's overall weight.
The iPad mini is the only current-generation iOS device without a Retina display. The full-sized iPad is thicker and heavier precisely because it has a Retina display and the LED and battery that come with it. Making the iPad mini with Retina but without making it a monster, and making the full-sized iPad thinner and lighter so it's no longer such a monster are obvious, logical next steps.
And Apple is always working on just that. The only real questions are: how do they get there and when. Reducing the amount of LED is part of the how. We're still waiting on the when.
The iPad line used to be updated once a year in the spring. Both the iPad 4 and the new iPad mini, however, were released just last fall. It'll be interesting to see how quickly Apple can get these next-generation models ready, and whether they return to a yearly release schedule, or keep up a faster pace.
It's a tough call. To fast and Apple will be accused of "obsoleting" and "screwing over" past generation customers. To slow and Apple will be accused of "falling behind" the competition and "no longer innovating". Which is worse?