As previously mentioned, human enemies won’t suddenly start wearing Glass and Ebony gear and kick your ass. The game’s difficulty is instead governed by enemy types and how often they're encountered. Difficulty correlates with rarity, so bandits and wolves, for example, will always be easy kills, while vampires and bears provide a greater challenge. Incidentally, the toughest mobs – giants and their mammoth herds – are passive creatures, and neither will attack unless provoked.
I was less than jazzed with how Skyrim handled the PC interface. I like the idea of the Favorites system, but would have preferred to be able to assign specific weapons to the number keys or to generally have a different item interface instead of scrolling through rows of item names -- if you're going to make the game for PC, you might as well find more ways to take advantage of the hardware than simply tightening up the graphics. The interface works really well if you have a gamepad but I felt it was rather cumbersome with the mouse and keyboard.
Skyrim also uses scattered books and references to enthrall you. You may not be a big fan of reading books in role-playing games, but even so, you should make an effort here. If you don't feel like reading up on Tamriel's rich history each time you find a volume, grab it and read it later--there are a lot of narrative tidbits that deserve to be read. Elder Scrolls fans will appreciate nods to events in prior games, and everyone can enjoy the bite-size tales contained therein, about vampires, noble heroes, and gods that bestow their blessings on their followers. Skyrim takes place hundreds of years after the events of Oblivion, and organizations you might remember have been restructured or are shadows of their former selves. But Tamriel's history is threaded throughout Skyrim's fabric, and some quests, such as one that begins with an invitation to a faraway museum, are great reminders of past misfortunes that the world has not forgotten.
Skyrim's Radiant Story system works for the most part; in addition to what Jeremy describes, it also presents itself in ways both subtle and obvious. Pick a side in Skyrim's civil war? Radiant Story makes your allegiance obvious by notifying you that you've just failed the quest objectives for the opposing side. Elsewhere, I'm tasked with investigating a local authority figure, but before doing so I had inadvertently caused a transfer in power via some other quest so that said authority figure no longer had his job. Therefore, a side effect: No need to investigate him.