I had the perception that
'CityProfile.com' would (for its names sake) place an emphasis on providing information that relates to the individual cities, giving each of them a dedicated and seperate area to attract contributions (posts). Grouping individual city sections together into regional divisions would make sense as well. If someone wanted information on Martinez, CA I would guess that they would not want the extra effort involved in trying to weed that specific information out of a section devoted to all of Northern California with a pot pouri of other completely unrelated topics thrown in for good measure.
Not everyone will include the term, 'Martinez' in their subject line making the search mechanism a less effective tool to find pertinent information that might otherwise be readily available if it were listed under a dedicated section. Even if they did, they wouldn't arrive at a discussion of the city of interest, but would instead only see what one lonely soldier has had to say about said topic.
Hope this helps...