The Elder Scrolls series is a first-person RPG adventure taking place in the world of Nirn, a land filled with many histories, races, cultures, and monsters. The Elder Scrolls themselves are pivotal to the games' stories, ultimately telling the future of the world, although its interpretations are entirely ambiguous.
Elder Scrolls V takes place in Skyrim, a Norse land where dragons rule. Major details for the game were sparse, but the narrator of the trailer dictates that the dragons fear but one being: Dovahkiin, the dragon born.
The trailer gave brave claims for its release, however: Skyrim will see release on November 11th, 2011. It is certainly expected to arrive on PC, though PS3 and 360 releases are also to be imagined, following the release pattern for Oblivion, the game's predecessor.