Scott Lemieux and Jack Balkin have two early takes on the Supreme Court's decision to hear the challenge to the District of Columbia's gun ban. My lack of legal expertise notwithstanding, Lemieux seems right on:
1) the most plausible interpretation of the 2nd Amendment, I think, confers an individual right to bear arms, although this is certainly not the only reasonable interpretation; 2) given this, D.C.'s draconian ban is (for better or worse) clearly unconstitutional, but 3) more reasonable gun control measures may be constitutional even if the right to bear arms is considered an individual right.
Balkin's argument, on the other hand, isn't as persuasive. He makes the same assessment of the legal questions as Lemieux does, but then speculates that one effect of the Court striking down the gun ban will be to hand Democrats a campaign issue and energize gun-control supporters. He may be right that feeling aggrieved at the hands of the Court can be a powerful motivator for activists, but it's incredibly difficult to see any Democratic presidential candidate actually trying to make gun control an issue in the 2008 election, regardless of how the Court ends up deciding the case. The political downside is far too great, and I suspect that most Americans (if perhaps not most DC residents) would find the District's ban on handguns excessive, to say the least.