The OP makes a good point? I'm not so sure of that.
In the last month, there have been 11 stories tagged with the "Australia" label. Second from the top, the stories have been about: the Pirate Party being registered, monitoring body temperature of firefighters, potential cure for aids discovered, major telescope threatened by bushfire, spy agency seeking permission to hack third-party computers, R18+ classification for video games, insulin's structure being cracked, orbital pictures of bushfires, drones used for bushfire forecasting, and the world's oldest fossils found. Most, if not all, are quite valid news for nerds stories.
There have been 30 stories specifically tagged as "usa", in that same time period. Granted, some stories are a little bizarrely tagged as "usa". Not sure why a story about unemployed chinese graduates is labelled such. Regardless, it's easy to see that Slashdot has a much larger USA bias.
And you know what, that's fine. It's good to read about things happening in the USA, just as much as it is for Americans to read about what's happening in the rest of the world. Including Australia. Stop acting insular. Enjoy learning anything and everything about the world around you. This is what, to me, truly defines being a nerd.