It's always bad form to quote yourself, but here's my own blog entry on the decision, and an excerpt from the entry -

http://tomfaranda.typepad.com/folly/2008/06/todays-2nd-amendment-supreme-court-decision.html

I was in the gym this morning when the Supreme Court decision ruling that the District of Columbia's law totally banning handgun ownership was unconstitutional. BUT, even the CNN commentators were surprised that it was only a 5-4 decision. They had expected a 7-2 or even unanimous deicision upholding the 2nd amendment "right to bear arms."

So a switch of one vote would have invalidated the common sense understanding of the second amendment! Amazing.