<joke>

The fact that you so naturally extrapolate "being the center of the United States" to "being the center of the Universe" also confirms a long-held belief of mine about the average American.

</joke>

Or that you're completely average :)

Another notable result of the 1980 census was that it was the first one where the majority of Americans lived west of the Mississippi River.

Not true[1]. Perhaps the "population center of mass" is west of the Mississippi, but that is a different statistic.

[1] http://wiki.answers.com/Q/What_it_the_population_west_of_the...

As an example of how this could be possible, imagine the population of the USA were 3: two people living in East St. Louis, and one person living in Hawaii.

It would be fun to actually compute the center of mass, knowing that people are not uniformly massive.

A good starting point might be average weight statistics on a per-state level. I doubt you could get any finer-grained information though.

Distance, as well as population, is a factor in the mean center of population. Even today there isn't close to a majority of the population living west of the Mississippi.

Good point, I only wish I'd seen it in time to fix my comment.