As a follow-up to this question, the next one is: Will we be able to simulate our interfaces how they look on the new high resolution display, even without owning an iPhone 4?

I guess that there is a formula that we can use to calculate the exact needed distance between our monitors and our eyes, to achieve the exact same visual effect of the Retina Display. This would help a lot to get things right. The first thing we need is an high resolution iPhone Simulator. I can't get any sleep until I know.