I have an iPad 3 and an iPad 2. The "retina" display is certainly a nice upgrade but it's hardly essential. This is obviously where the industry has been heading for a while and the only thing interesting about it here is that Apple's supply chain dynamics makes it possible for them to get 6-12 months ahead of the competition.
Some text looks like crap on the old screen (iPad 1), with visible aliasing and color fringes - making zooming absolutely required for reading. Not so with the retina display.
