Anandtech's look at the one S display:
It isn't so much the brightness though, more that it just looks pure white and doesn't have a warm yellow tint to it (GS 2 was horrendous for this)
Side by side with my calibrated dell U2311H, you would be hard pressed to notice the difference as that is how good I find the whites on the one S, maybe I have a poor U2311h when it comes to whites though....
Trying to find the photos I took of my S when white was displayed and came across this:
http://forums.overclockers.co.uk/showpost.php?p=21639371&postcount=22
3. Display - even if font details can not compete with X or my GN I prefer the better blacks of the S compared to X and the better whites compared to my GN. Also this Amoled is not blueish or greenish, like S2 or GN.
Here are just a couple of photos of the mobile displaying a white screen in the dark, one at 50% brightness and 100% brightness, photos were taken by the desire. Doesn't look quite the same as what it does with your own eyes but that is the best I could do, sorry
There is also a video comparing it to the GS 3, trying to find it now.
And many many other people on xda who had both gs 3/gs 2 and one s have said the same.
Perhaps I was just one of the lucky ones and the gs 3 I seen was a bad one as this sort of stuff varies a lot, no display panel is exactly the same as every expert in the display tech. world will tell you, in fact ask PCM 2 in the monitor thread.
Don't exaggerate anything, after all if I did, then why are there many other user opinions and some review sites saying the same then?
The whites aren't that bad on the GS 3 that it makes you want to change your phone for a better one but I found that it was noticeable even when not side by side with the one S etc.
I am not blinded by brand loyalty unlike a lot of people, if something is crap, I will say it, if something is good/better I will admit regardless of the brand and generally why I think is backed up by "hard evidence"

(most of the time

)
In fact I think you've said something in this thread about exynos based devices being tricky with flashing?
Not quite that, but this:
Easy to flash, crap to develop ASOP ROMs and things like that for due to the closed source nature of the exynos code.
CM developers are ****ed of with samsung due to that and iirc were at the point were they no longer wanted to support galaxy devices.
Yeah, I think if I did get a GS 4, I would root and flash a touchwiz based themed stock android ROM/JBD theme as that is the only thing I really hate about touchwiz these days.