Most people visit a search engine when they are looking for a product or service of some sort and conduct a search on a rather broad topic. Someone looking to buy a house in their own town might type the keywords, "real estate" into the search engine. When they are returned a list of Web sites starting in Alaska showing all the real estate in the world, over 300,000 sites from Alaska to Wyoming, they quickly see the value of narrowing their query. The next search they conduct will be something like, "Virginia Real Estate." This will give them something more manageable.
What this should tell any Web marketer promoting any product of regional significance is to "regionalize" their site description and keywords where appropriate. A Realtor client of mine learned that by keeping his site title and description stuffed with "VA" and "Virginia" he ranked well above other similar sites who didn't pay attention to this technique.