callivert - 2:49 am on Feb 17, 2010 (gmt 0)
Above, I see good, true opinions, but I do not see a direct answer to the OP's question. Let me ask it again.
In Google Webmaster Tools, if I set my "Geographic Target" to "United States", will I earn more money, or less money?
That's not the same question at all. The OP asked about sites that "target" the US in general. There are many ways to target.