I was skeptical about quests initially, but tried it out today. My first quest, while a bit lackluster, did net me about a million coins with minimal effort, so I really can't complain. I imagine as we go along, they will get more complex. I agree with Pythonis in that I hope they will eventually make the quests more team oriented. I think they are starting off simply to see how it goes and to work out the programming bugs before getting more ambitious.
What I love about the FT quests is they are not mandatory for advancing levels: You play them if you want but you're under no obligation to if you don't. Just my two cents.