The Social Security Administration announced that the contribution and benefit base for wages and self-employment income earned in 2011 is $106,800, the same figure as 2010. No limit will be imposed on the amount of wages subject to the Medicare tax.
Additionally, the recently passed Tax Relief, Unemployment Insurance and Job Creation Act of 2010 reduces Social Security tax withholding from 6.2 percent to 4.2 percent of employees' wages in 2011.
More details at: http://www.ssa.gov