Time to update some old information regarding AMOLED's and Pentile sub-pixels.
The display in the new Samsung Galaxy S2 is Super AMOLED+. The "+" part refers to the true RGB sub-pixel arrangement, not the RGBG pentile arrangement they used in the original Galaxy S.
http://www.oled-info.com/super-amoled-plus-resolution-explained
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Only problem being display burn-in, welcome to back to the 90-ties! I had a Samsung Galaxy S with Super AMOLED and the status bar burned in after a month of use or so. Don't get me wrong, the display had great, vivid colors, but at the price of display burn-in. (also in my eyes, the display wasn't any better than the iPhone 4's)