I'll leave further commentary to our excellent lawyers, but here's the video:
The CNN legal correspondent's comments included the following:
This was a train wreck for the Obama administration. This law looks like it's going to be struck down...All of the predictions including mine that the justices would not have a problem with this law were wrong.
...The only conservative justice who looked like he might uphold the law was Chief Justice Roberts who asked hard questions of both sides, all four liberal justices tried as hard as they could to make the arguments in favor of the law, but they were -- they did not meet with their success with their colleagues.