This is incorrect. SCOTUS will decide the constitutionality of the law.
http://www.scotusblog.com/2011/11/court-sets-5-12-hour-hearing-on-health-care/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+scotusblog%2FpFXs+%28SCOTUSblog%29
This is easily the best website for all things supreme.
They have certainly been asked to decide it, but they can rule that the issue isn't yet ripe.
At least one case at the Circuit level was decided on the basis of "standing," of some form. IIRC, it was the one where a state passed a law making federalized purchase mandates illegal in that state.