The majority opinion does not rule on the constitutionality of various federal firearms regulations. It does not even strike down D.C.'s licensing requirement. Nor should it have. The Constitution gives the Court the authority to judge only the controversy before it, in the way that controversy is presented by the parties. Federal gun laws were not at issue here. The plaintiff, Dick Heller, challenged the arbitrary application of the licensing requirement, not its facial validity. These issues were properly left for future cases, such as this one: http://www.chicagoguncase.com/
The good news is that the Court laid a strong foundation for future court challenges to gun control. The Court cloaked the Second Amendment with the same protection it has recognized for the other rights protected by the Bill of Rights. While this level of protection allows some regulation to contextualize the exercise of rights, it is the highest level of protection accorded rights in the U.S. legal system. This is the foundation upon which future cases will be built:
"JUSTICE BREYER correctly notes that this law, like almost all laws, would pass rational-basis scrutiny. ... But rational-basis scrutiny is a mode of analysis we have used when evaluating laws under constitutional commands that are themselves prohibitions on irrational laws. ... In those cases, “rational basis” is not just the standard of scrutiny, but the very substance of the constitutional guarantee. Obviously, the same test could not be used to evaluate the extent to which a legislature may regulate a specific, enumerated right, be it the freedom of speech, the guarantee against double jeopardy, the right to counsel, or the right to keep and bear arms. ... If all that was required to overcome the right to keep and bear arms was a rational basis, the Second Amendment would be redundant with the separate constitutional prohibitions on irrational laws, and would have no effect. "
This is a good day for liberty, but it is far from the end of the fight. Securing the full measure of liberty will require years of litigation funded by regular people who care about liberty and a good Supreme Court going forward. On that latter point, notice that all the Justices appointed by Democrat Bill Clinton voted against the majority's expansive view of American liberty. Keep that in mind this November.