In the second preemption decision, the Court ruled 8-1 in Preston v. Ferrer (06-1463) that federal law prevents the referral of disputes which the parties had agreed to arbitrate to an initial review by administrative agencies under state law. In other words, if the federal law says you can arbitrate something, and the state law says it must be reviewed by an administrative agency, you can arbitrate it. This opinion was written by Justice Ginsburg, while Justice Thomas dissented.
The third preemption ruling by the Court was in Riegel v. Medtronic (07-179), by an 8-1 vote with Justice Scalia writing the opinion and Justice Ginsburg alone in dissent. This ruling said that the Food and Drug Administration's pre-market approval of the safety and effectiveness of medical devices bars state court damage lawsuits, striking a significant blow to product liability lawsuits.
So product liability, arbitration laws, and conflicts with tobacco litigation were preempted by the Supremes.
There were two other cases decided. In the first, LaRue v. DeWolff, Boberg & Associates (06-856), the Court ruled unanimously that individuals who, while participating in retirement plans covered by ERISA, lost money due to the fault of plan managers or administrators have a right to recover money losses. The opinion was written by Justice Stevens.
In the last decision issued, the Court decided 7-2 in Danforth v. Minnesota (06-8273) that states can under their own laws grant to prisoners the retroactive benefits of Supreme Court criminal law decisions & even if the Supreme Court itself has declined to apply those decisions retroactively. Justice Stevens wrote for the majority, while Chief Justice Roberts and Justice Kennedy dissented.
Whew! That's a lot to digest. Good luck!