Apple today announced its third-generation iPad. As expected, the third-generation tablet features a 2048 x 1536 “Retina” display—for a total of 3.1 million pixels—and is powered by the new quad-core A5X processor. According to the company, the new processor was “designed for Retina display”, and offers “four times the performance” of the Tegra 3 processor. Also new is a five-megapixel, backside-illuminated…