yeah, the screen is awesome. I was doing A/B comparisons on web pages and here's what I found:
1. at normal distance there is a "just better" factor. You might not be able to put your finger on it, might not instantly jump out at you, but the 4 screen is unquestionably the better screen in a blind test.
2. at NORMAL DISTANCE you can make out finer detail when you look at it. A great example is a normal 10pt web page. at normal viewing distance the normal type is unreadable on a 3GS, and at closer examination you can see that it is actually rendered unreadable. It is all a blur even right next to your eyes. At normal distance (and with great eyesight) you can still read the 10pt text on the 4. Right next to your eyes you can see that every letter is perfectly rendered on the four.
3. at closer inspection you can start to specifically see some of what you started to notice in point 1. No jaggies on fonts. Readable smaller print. Much deeper colors and blacks. No "screen door" effect at close up, and no hazy effect at normal distance, caused by the lower DPI of the 3GS screen.
I don't doubt that 10 out of 10 people would pick the 4 screen when asked which looks better. And that's all that really need be said. No it won't be mind blowing for many. Yes most won't be able to give you a well reasoned why it looks better. But hold it up next to the Evo, 3GS, Droid, whatever.. and I promise you every single person will agree that the 4 screen is just fucking sharp.
anyway, as soon as apple puts up the white pre-orders I'm on top of the 32GB one. But in the meantime I'm fine with my 3GS, and I know when my daughter gets the 3GS (her first phone, currently on a 2nd gen touch) she is going to go through the roof