The gameplay is easy once you have chosen the skills you will use. There are difficulty modes. Normal, Nightmare and Hell. Obviously each mode will get more difficult starting from Normal and the harder the difficulty, the more quality items and more experience for your character. There are also hot keyes that you can designate on your keyboard to switch skills quickly.
Graphics are very good.
Terrain, Detail, and items your characters where are better. The sound on the game is excellent. The background music is good and the action when you are fighting keeps you on your toes. The game is much better if you play it on Blizzards internet service battle.net. I was lucky enough to get in the stress-test, and I was amazed.