The FICA tax reduction was part of the deal renewing the Bush Tax Cuts in December.
If the annual tax rates were reduced, not just the amount withheld, then I certainly stand corrected.
This is what the government itself says: It’s a FICA tax cut — not JUST a withholding cut, as I was stubbornly saying — BUT the amounts will get repaid to SS by “The general fund,” in other words, general tax revenues. They’ll have to raise OTHER taxes (or cut spending that otherwise wouldn’t need to be cut) to “pay for” this “tax cut.” It’s all smoke and mirrors.
http://www.ssa.gov/oact/progdata/taxRates.html
(in the footnote)