The predicted effects of us falling over the cliff if no deal is reached by the end of the year:
US NEWS report
The Congressional Research Service (CRS), along with the CBO, and anyone who lived through the stagnant economy during the Bush tax cuts era concluded:
Multiple CRS Reports Show Tax Cuts for Rich Will Not Harm Economic Growth
The New York Times recently reported that a Congressional Research Service (CRS) report was "withdrawn from circulation" at the behest of Senate Republicans. The CRS report finds no relationship between upper-income tax rates and economic growth, undercutting Republican claims that an extension of the Bush tax cuts for the wealthy is necessary for economic growth. Senate Republicans called the report's validity into question, and CRS eventually withdrew it. However, the report's findings are only the latest in a series that suggest only a tenuous relationship between the economy and upper-income and capital gains tax cuts.
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History and facts tells us that the times of highest economic growth coincide with the times of highest top tax rates. For a recent example, just compare the economy under the Clinton era tax rates with the economy under the Bush tax cuts. It's a no brainer, really.