Turns out Sudoku (new in GNOME 2.18!) is the output of a Japanese game company called Nikoli. Nikoli gives much of the credit for their creativity and prodigious output to their community of puzzle solver-readers, who suggest new games and refinements to old games to Nikoli. As icing on the community production cake, they plans not to trademark future games in the US in order to encourage their growth. Full NYT story here.