Geography play a huge part in any marketing program. This is even more true when it is applied to Internet Affiliate marketing. Imagine the millions of potential eyeballs just waiting to buy your merchant's product and make you rich (cue record needle scratching across a record). Imagine the potential to make OR lose enormous amounts of money.

Depending on what kind of affiliate marketer you are, narrowing your marketing scope is probably one of the most important things that you could do. Why waste advertising dollars selling American made woolen sweater to people in Kenya, Africa who, A do not need sweaters and B, are outside of your merchants shipping area? It's all about Geo-targeting. And it can be very powerful and effective.

The up side
The up side is actually the down side. By knowing where your traffic is globally, you can limit you expense in finding and directing quality traffic to the appropriate merchant(s).

Target your audience
If you are selling American truck parts it makes no sense to waste time and money by advertising