Intrinsic rewards and replayability in Card Hunter

People who study fun in games, gamification, and how to motivate people have written a lot about the concept of intrinsic vs. extrinsic rewards. The idea is that something which is inherently more fun is more motivating than having to do a boring activity for a reward later. Of course that is more of a theoretical concept, because whether an activity is fun in itself or not is not so easy to determine. I think that for most people the activities in their first MMORPG were inherently fun, but be

World of Warkraft...