I have plans to sell my iPad 2 to get a 3, but if they could make an 8 inch tablet with identical specfications to iPad 2, I might just get that purely for the weight saving. The damn things are too heavy, and a weight reduction would be just as appealing as a retina display.
There have been zero leaks of parts for such an iPad meaning if it is indeed coming it won't hit the same day as iPad 3. You'd have a long time to wait watching people with their shiney new iPad 3's.