It's totally true: Foursquare, Gowalla, etc. appeal most directly to a young tech-savvy market. Basically, SF.
Companies like AngiesList and Groupon serve a broader market and are not based in SF area. So, they get less attention. But, these are bringing in far more revenue and will likely last longer.
Companies like AngiesList and Groupon serve a broader market and are not based in SF area. So, they get less attention. But, these are bringing in far more revenue and will likely last longer.