Yeah, the thing is that not only has it been done before:
...it's been done with more careful thought and research into the history and culture of the continental US, too:
You can read about the reasons for dividing it up here. His book has been on my reading list for a year or two now. Don't know if it's any good but someone who understands the influence the Dutch have had on NYC must know at least some history.
PS: the Las Vegas / LA combination was filtered out before their heuristics even came into play:
When filtered by distance (d < 160km)...
But hey, pretty graphs!