Richard Kogan & Robert Greenstein have posted President Portrays Social Security Shortfall As Enormous, But His Tax Cuts And Drug Benefit Will Cost At Least Five Times As Much on the Center on Budget and Policy Priorities web site.  Here is the conclusion:

The President has suggested or implied that Social Security presents a greater budgetary problem than Medicare or his tax cuts, and that the Medicare prescription drug bill will help to reduce the overall cost of Medicare by averting unnecessary hospitalizations. Analysis conducted by the Social Security and Medicare Trustees and actuaries, the Congressional Budget Office, and the Government Accountability Office, among others, show that such views are mistaken.

The reality is that the Social Security shortfall, while sizeable, is not gargantuan, and it is not necessary to alter Social Security’s basic structure to close the shortfall. Both rising health care costs, which drive much of the projected growth in Medicare costs, and the long-term cost of the President’s tax cuts pose much larger budgetary problems.