From the WSJ: Get Ready for a 70% Marginal Tax Rate Some argue the U.S. economy can bear higher pre-Reagan tax rates. But those rates applied to a much smaller fraction of taxpayers than what we're headed for without spending cuts. http://online.wsj.com/article/SB10001424052702304911104576443893352153776.html
Now that the repubs run congress and the next Pres will almost surely be a repub too, theres really no need to worry about a higher marg rate.