Ubuntu's Local Community Teams are an attempt at broadening the geographic user base. There was a goal at one point to get one team in each US state, and there's probably been other such goals for worldwide coverage.

I'd add that it'd be nice to see more ethnic minorities joining in. It's a bit depressing to go to an event with 700 people and count the people of color on one hand, the women on two hands, and folks with disabilities on one hand as well. That last one really can be fixed with code... if a person can't try your software due to a11y issues, they're not terribly likely to contribute.