Is the payroll tax cut applied to both employer and employee?

yes

ABSOLUTELY NOT!! (Not sure who wrote 'yes.)

The IRS regulations state that the employee tax rate for social security tax in 2011 is 4.2%. The employer tax rate for social security remains unchanged at 6.2%. The 2011 social security wage base limit is $106,800. In 2011, the Medicare tax rate is 1.45% each for employers and employees, unchanged from 2010. There is no wage base limit for Medicare tax. Employers should implement the 4.2% employee social security tax rate as soon as possible, but not later than January 31, 2011.