What is the percentage amount that the employer pays to FICA?

As of the new law passed in Dec 2010:

The tax is payable on the first $106,800 of earnings. Earning are defined slightly differently for this than what is used for withholding, (or other things). Additionally, a portion of what was a total of 15.3% tax equally paid between employer & employee - or entirely by self employed (half employer paid, half employee), is dedicated to Medicare and has no maximum earnings limit.

HOWEVER:

Under current law, employees pay a 6.2% Social Security tax on all wages earned up to $106,800 (in 2011) and self-employed individuals pay 12.4% Social Security self-employment taxes on all their self-employment income up to the same threshold.

For 2011, the Senate passed 2010 Tax Reform Act gives a two-percentage-point payroll/self-employment tax holiday for employees and self-employeds. As a result, employees will pay only 4.2% Social Security tax on wages and self-employment individuals will pay only 10.4% Social Security self-employment taxes on self-employment income up to the threshold.

The maximum savings for 2011 will be $2,136 (2% of $106,800).

The amount paid by the employer will not change and will be that same 2% more than the employee.