The case in particular revolves around a Washington DC (unconstitutional) ordinance that bans handguns, or requires their disassembly. But upholding what a federal judge has ruled, that such an ordinance is unconstitutional, the principle of course (though plain to all) has ramifications on all gun measures that states and the federal government have (unconstitutionally) passed--i.e. mandatory registration, IDs, concealed carry, transportation between states, etc. The current gun laws would have been immediately decried by the founders which included this in the Bill of Rights.

"As civil rulers, not having their duty to the people duly before them, may attempt to tyrannize, and as the military forces which must be occasionally raised to defend our country, might pervert their power to the injury of their fellow citizens, the people are confirmed by the next article in their right to keep and bear their private arms."
Tenche Cox, 1789 on the 2nd Amendment