At a press event in London on Thursday that it described as an "unpacking," Samsung indeed rolled out an impressive array of hardware and software enhancements that the company hopes will help it retain its ranking as the top cellphone-maker in the world. The biggest feature (literally) most consumers will notice is a stunning 4.8-inch Super AMOLED screen. That's about a half-inch larger than Samsung's Galaxy S II, and significantly bigger than the 3.5-inch high-resolution display on the Apple iPhone 4S. Despite the large screen, the S III actually is a bit thinner than the iPhone 4S (8.6mm vs. 9.33mm) and is slightly lighter as well (133 grams vs. 140 grams). Besides the screen, consumers are likely to be most interested in the Galaxy S III's operating system and whether it is closing in on Apple's iOS, which has been widely considered the market leader since the iPhone was introduced in 2007. The Galaxy S III will run the so-called Ice Cream Sandwich v...