I got to play with one at the TMobile... have to say, the AMOLED screen isn't all bad. Yes, the pixelation is noticeable if you are coming from a phone without it... but I turned the brightness all the way up on my Sensation, compared the two... and it is a noticeable upgrade in terms of sharpness and clarity, though you have the slight pixelation to show for it.
I am having a bit of a hard time getting over that, though if I adjust my hold and move the phone back a little and turn down the brightness I can't see it all that much... and I think I could live with a little pixelation.
I might actually return my sensation (got it for $100) and get the One S on value pricing (manager said she thinks its gonna be $150, though I think it'd be closer to 200-250 for payment plan)