Image from RepairLabs
As expected, the iPad 3 will reportedly include a 2048x1536 Retina Display, be nearly identical physically, and use the A6 processor. The A6 processor, however, is claimed to have a dual-core chip, not a quad-core one, at least according to his sources:
What is surprising, however, is that our sources say that the A6 will not be a quad-core chip, but will remain dual-core. We've previously had heard that the device would have a quad-core CPU as well as an LTE cell radio on-board, but at least part of that story wasn't accurate.
While a dual-core A6 is certainly possible, Topolsky's iOS device sources haven't had the greatest track record. In early 2011, his sources claimed that the iPad 2 would include a "super high resolution display" as well as an SD card slot, and a "completely redesigned" iPhone 5 to come in summer 2011. Topolsky did backtrack on those predictions, but not until the week before the iPad 2's launch.