Posner wrote the opinion, holding that:
The Supreme Court’s interpretation of the Second Amendment therefore compels us to reverse the decisions in the two cases before us and remand them to their respective district courts for the entry of declarations of unconstitutionality and permanent injunctions.
Nevertheless we order our mandate stayed for 180 days to allow the Illinois legislature to craft a new gun law that will impose reasonable limitations, consistent with the public safety and the Second Amendment as interpreted in this opinion, on the carrying of guns in public.
The decision is here [pdf]
Williams is correct. Scalia made it clear in Heller
that the right wasn't absolute.