The Romer's (remember that Christina Romer was the head of President Obama's Council of Economic Advisors) have a paper out that shows much higher wealth destroying, "contractionary" effects for tax increases than economists had previously estimated. Most of the effect comes from declines in investment. This is particularly important both because it is a particularly good paper by leading economists and because it is an "admission against interest," in other words it is an argument that supports the policy preferences of the right though it comes from researchers on the left.

The debate about higher taxes on the rich should not be about whether we can raise more tax revenues by lowering tax rates so much as whether we will be a wealthier society by lowering tax rates.

Berkeley Economist Christina Romer