From Mark. Blog.: "Hot damn, don't buy an iPad! Or if you already have, you poor bastard you, sell it on eBay! In January, we're going to have a new iPad (I'm calling it the iPad Unicorn) with a sick Retina display! If you believe that, or if you can follow that logic, I'm going to save you some trouble now and tell you it's not going to happen." - Mark Trapp from Bookmarklet

To be fair, Apple calls it a 'Retina Display' because that dpi is indiscernible at the distance a phone is usually held. An iPad is held further from the eye so while its current display doesn't qualify as a 'Retina Display' the DPI could be bumped to the point where, at an iPad's distance, the pixels are indiscernible without having to go close to 326 dpi. My guess is that 260dpi or so would do the job. - Kevin Fox

I guess you can argue about the optimal viewing distance of the iPad (I admit I was using the same distance as an iPhone for my assumptions), but even at 260ppi, you're talking about a resolution that's comfortably above 1080p (if I'm not mistaken, 2017x1513 on a 4:3 display) - Mark Trapp

I wonder how long It would take for a mobile device to run today's top graphics at that resolution. - Rodfather

I'm salivating at the thought of such a thing. - Geoff Schultz {TF}

Kevin: based on your insight, I believe a "retina display"-qualifying iPad would only need a pixel density of 144ppi, which is only marginally better than the current 131ppi. It's so minor I'd argue then that it wouldn't qualify as a major upgrade at all (I'd wonder if Apple would even bother and claim the current display is good enough until it could come up with something truly revolutionary, like it did with the iPhone). - Mark Trapp