"Centroid" is, like, a center point balancing the competing claims of population, geography, transportation, and commerce?

So what did turn out to be California's centroid, anyway? Was it LA (or in the LA area) or did the competing claims of south and north put it at some odd spot between them, like SLO or Fresno? What about other states with a heavy population crunch towards one corner, like Michigan, Illinois, or South Dakota?

Come to think of it, if confidentiality requirements don't prevent you, post the whole list. It'd fascinate us geography geeks.