As far as comparison between LCD and AMOLED is concerned, what is so funny about, say, the difference in contrast ratio: 100,000 to 1 for Samsung vs 800 to 1 for iPhone 4?
What's funny is that you've based your opinion off the information provided by a website called oled-display.net. Yeah, no bias there at all. Also funny that the only direct comparison they show in an article titled "Iphone-4 Retina Display LCD-IPS vs Super AMOLED" is a picture titled "Super-Amoled vs Iphone 3GS LCD IPS". Very telling.
Also, everyone with half a brain knows that contrast ratios are the biggest scam running in the world of display technology. There are no standards governing the reporting of these numbers, and anyone who has bought a flat-screen TV is familiar with the ridiculous gamesmanship of constantly increasing huge numbers, which culminated in the absurd Infinity:1 ratio being used by some companies. Anyone who wants to actually learn something about displays, and not just read FUD spouted by a well-known Apple hater on a web forum, can check out an excellent article here: http://www.maximumpc.com/article/features/display_myths_shattered