The debate on higher education and its value continues forward. Graduates make about 70% more than non-graduates but at what level do the returns start to diminish. An argument brought forward in the Economist states that real earning power of higher education is declining.
The Economist Article
There is a point and certain fields that the return of higher education may not be worth the cost. This all depends on what you are trying to accomplish in your life. Up to the MBA level advanced degress seem to have some relevance in the market.
Unless you are going to be a researcher or an academic the obtainment of a PhD is worth much less. You may make descent money but it doesn't seem to significantly improve. The type of work changes but the overall value to the market seems to be less.
There is also a problem with being overqualified and people won't hire you for industry jobs. It would seem that a manager would love a doctor for a discount price. The problem is they don't want to hire someone who has more education then them knowing that eventually they may be replaced.
Likewise, where you get your degree is important. Call it "elitist", unfair, or call it snobby but the ugly truth is that a Harvard or Yale degree is worth more than your local community college. These are brands. Education may be great but actual performance is questionable.
You may also consider what field you get your degree in. Certainly, philosophers are important to society during our massive transition but they are not likely to be paid as much as say someone in the medical field which is supported by large insurance industries or in the technical fields that have strong corporate utility.