Sharing Opinions: The AI will share their opinions of other leaders with you if they deem you a trustworthy ally.
Map Trading: Sell World Maps upon discovery of Military Science. Cost goes up depending on the quality and quantity of terrain that is to be discovered - don't be surprised to chalk up a lot of cash/luxuries/your map for a map! Maps that are equal (no unique territory between two civilizations) are worthless.
Technology Trading: Upon discovery of Scientific Theory, allows you to sell technology with other civilizations. The cost will be determined by how many turns left this technology has to be researched (by the purchasing civ). By default, Research Agreements are disabled, but you can re-enable them (and disable this feature) in Advanced Options.
Request Help: Replaces "Demand" with civilizations whom you've declared a Declaration of Friendship with (no diplomatic penalty, AIs will give help if they're in a better shape than you)
Generous Offers: AIs whom you have a Declaration of Friendship with will offer you help if you need it (if you're low on GPT/Gold they will donate some, if you're low on happiness they will donate a luxury).
Vassalage: Enslave your defeated foes and create vassals! Vassals are your puppet states. You swear protection to them, and in turn, your Vassals provide you with tribute.
