It stands.

I'm still not quite ready to believe that Justice Roberts joined the liberal wing in the majority. I would not have ascribed a 1% chance of that happening.

Excerpts follow from the SCOTUS(live-)blog.

SCOTUS holds that mandate violates the Commerce Clause, but is constitutional under legislative branch's power to levy and collect taxes.

In his opening statement in dissent, Kennedy says: "In our view, the entire Act before us is invalid in its entirety."  

Amy Howe: 

In Plain English... The Affordable Care Act, including its individual mandate that virtually all Americans buy health insurance, is constitutional. There were not five votes to uphold it on the ground that Congress could use its power to regulate commerce between the states to require everyone to buy health insurance. However, five Justices agreed that the penalty that someone must pay if he refuses to buy insurance is a kind of tax that Congress can impose using its taxing power. That is all that matters. Because the mandate survives, the Court did not need to decide what other parts of the statute were constitutional, except for a provision that required states to comply with new eligibility requirements for Medicaid or risk losing their funding. On that question, the Court held that the provision is constitutional as long as states would only lose new funds if they didn't comply with the new requirements, rather than all of their funding.

I'll assemble various reactions later today.

Update: A fairly hilarious Twitter aggre-reaction. The first Tweet there is in response to CNN's initial webpage update, quickly pulled down, that said the ACA was rejected. And Republicans in Congress Tweeted that the law had been struck down, and then deleted them once they figured it out had it explained to them by a fifth-grader.

Update II: Lyle Denniston of SCOTUSblog:

Salvaging the idea that Congress did have the power to try to expand health care to virtually all Americans, the Supreme Court on Monday upheld the constitutionality of the crucial – and most controversial — feature of the Affordable Care Act. By a vote of 5-4, however, the Court did not sustain it as a command for Americans to buy insurance, but as a tax if they don’t. That is the way Chief Justice John G. Roberts, Jr., was willing to vote for it, and his view prevailed. The other Justices split 4-4, with four wanting to uphold it as a mandate, and four opposed to it in any form. 

Update III: Fox News' losing efforts to declare ACA unconstitutional. Their only recourse now is to impeach... Chief Justice Roberts.

Update IV: "(T)he ‘Scalia Freakout’ ended up being the big tell about this morning’s ruling."

Update V: Mitt Romney just had his reaction televised, and you would have thought his dog had died. Well, maybe his dressage horse. Then again, maybe his wife. OK, his political fortune. Seriously, I've seen more joy expressed in eulogies.

Harold Cook has a sly take:

So to review: the Supreme Court concluded that health care reform is constitutional, including the individual mandate (although SCOTUS apparently characterized it as a tax). The Republicans will try to spin the hell out of the "tax" part, even though it's only a tax for those Americans who fail to do what is required under Mitt Romney's health care plan.

The individual mandate only exists because it was the mechanism Republicans said they liked, and the mechanism their own Presidential nominee said is essential. Then the Republicans immediately decided that their own plan was terrible, evil, and unconstitutional, because it happens to be signature legislation of a President they hate, and Republicans sued to have it overturned.

So remind me again - what aspect of affordable health care to Americans can Republicans take credit for? Zero. Less than zero. They even fought like hell against their own funding mechanism to ensure its failure. Fortunately, they have apparently failed.

Those 14 original Republican Attorneys General who sued to overturn the plan? They'll spend the rest of the day complaining, and rename "Obamacare" to "the Obamacare Tax," all without presenting a new idea of how they would have made health care affordable.