Anyone who has played Dark Souls knows the world of Lordran is violent, dark, and sometimes even disturbing. Based on the many recent trailers it is safe to assume that Dark Souls 2 will feel very similar, so it is surprising to hear that the game has earned a 'T for Teen' rating from the ESRB. According to the ESRB site, the game was rated this way for "Blood and Gore, Mild Language, Partial Nudity, and Violence". To compare, Dark Souls was given an 'M for Mature rating' for "Blood and Gore, Partial Nudity, and Violence." The games contain the same descriptors, so the difference must lie in the degree to which they are used.
While the T rating definitely surprised me, it doesn't worry me at all. Dark Souls 2 doesn't need a mature realistic world to immerse me. The world shown in the trailers doesn't seem any less frightful or forgiving, and the new rating could simply be the result of a change in values at the ESRB.