The NY Times has a forum today titled "Is the health care law unconstitutional?" with varying viewpoints on display. Randy Barnett has his entry on the Volokh Conspiracy and here's the concluding paragraph about the individual insurance mandate:
Does the text of the Constitution authorize this exercise of power? No, it doesn’t. Has the Court ever before upheld this claim of power? No, it hasn’t. Can the challengers get this mandate invalidated? Yes, they can.Obama will probably take another cue from FDR and try to pack the Supreme Court. Anything goes!