So we took a look. We had to go deep into the article to find it, since the constitutional law types that write articles like this find preemption boring, but sure enough, it's covered. Here's what the SCOTUSblog piece has to say about preemption post-Stevens:
Preemption is the principle that federal law trumps state law. It is grounded in the Supremacy Clause of Article VI of the Constitution, which provides that “[t]he Constitution, and the Laws of the United States . . . and all Treaties . . . shall be the supreme Law of the Land.” Although formally a constitutional issue, preemption questions most often involve the construction of a federal statute (or sometimes a regulation) to determine whether it precludes a state (or local) law. The Court’s preemption decisions have not pointed in a consistent direction and have tended to turn on their particular context. Two significant recent decisions have ruled against preemption claims, however, and Justice Stevens authored the majority opinion in both. One was decided six to three, but only five members of the Court joined Justice Stevens’ opinion. Wyeth v. Levine (2009). The other was five-to-four. Altria Group v. Good (2008). Preemption is thus an important area of the law that could shift with Justice Stevens’ departure towards finding greater federal preemption and thus reduced state authority. The principal consequence would be to allow fewer state tort suits to proceed.So now you know as much as we do. We certainly hope that SCOTUSblog is right on this one.