Can money buy happiness?

I'm giving a talk on happiness this week, so I've been immersed in the research on causes and correlates of happiness (as well as measurement issues and a host of other topics). This field is often quite complex. For example, the research on the relationship between income and happiness has found that:

• Within nation, there is a very slight correlation between income and happiness, which is only significant at the lower levels of income (that is, the very poor are at greater risk of unhappiness).
• Across nations, there is a fairly substantial correlation between the GDP of the nation and the average happiness of its citizens -- wealthier nations have happier individuals, on average.
• Although there have been substantial increases in affluence within nations historically, this has not resulted in increases in happiness -- that is, although there is higher average affluence in the United States today than in the 1940s, Americans are not happier, on average.
• Individual increases in income are not consistently related to increased happiness. Getting a raise at work may result in a brief increase in happiness, but it is generally temporary (the person drifts back to their previous level of happiness). Studies of lottery winners find that they report a slightly higher level of happiness, but also considerable difficulty and unhappiness as well.
• Those who value materialist goals over other (non-materialist) values are less happy later in life.

So, looking at all this data, does money bring happiness? Discuss amongst yourselves.