On the net, while being made iPad3 expected to be released around April of next year, has flowed depth specification information.
1.iPad3 design almost unchanged iPad2.
(Just like a design change to the iPhone4 just iPhone4S.)
2.iPad3 is equipped with high-resolution Retina display resolution and twice iPad2. Therefore, the thickness increases slightly.
3.iPad3 seems to be employed with large RAM and a quadcore A6CPU.