Daniel Kahneman recently answered a variety of questions from the Freakonomics crowd. On the relation between pleasure, utility and happiness:
[B]eing happy (on average) in the moment and being satisfied retrospectively are not the same thing. People are most likely to be happy if they spend a lot of time with people they love, and most likely to be satisfied if they achieve conventional goals, such as high income and a stable marriage.
Sam Harris interviewed Kahneman earlier this week. How Kahneman's thoughts on happiness have evolved:
I used to hold a unitary view, in which I proposed that only experienced happiness matters, and that life satisfaction is a fallible estimate of true happiness. I eventually concluded that this view is not tenable, for one simple reason: people seem to be much more concerned with the satisfaction of their goals than with the achievement of experienced happiness. A definition of subjective well-being that ignores people's goals is not tenable. On the other hand, an exclusive focus on satisfaction is not tenable either. If two people are equally satisfied (or unsatisfied) with their lives but one of them is almost always smiling happily and the other is mostly miserable, will we ignore that in assessing their well-being?
My take on Kahneman's new book here.