Having hosted a weekly DM'd Neverwinter Nights campaign for the last 8 months straight, I have picked out some observations about gamers.
1 Players have more fun interacting with each other than with my world. Even though the world is necessary to provide a place to do so.
2 If a player doesn't have a choice, don't give them a choice.
3 Prepared adventures are never as exciting as adventures that are improvised around the players' current situation.
4 All you need for an adventure are friends, something to do, people to see, places to go, prizes to earn, and stuff to kill.
5 Some players can initiate their own quests proactively, but MOST are not accustomed to that privilege. Generally, offer varied choices and make it clear what their choices are, or you might just find yourself sitting their doing nothing.