Limited Competition in Secondary Markets

I recently took the AdWords professional exam again and the section I failed was international search. It is easy to do that because if you are primarily focused on the US market there are parts of search you can't appreciate until you see them. When I was in Canada about a month ago I noticed PageRank 4 pages dominating search results where you would need at least 100x the link equity to compete on Google.com. Some of the most valuable US keywords only have a couple advertisers in Canada.
In The Slums of Search, Gord Hotchkiss wrote:

At Enquiro we actually did studies and asked people why they were reluctant to click on sponsored ads. The most common response was that they didn't trust the advertiser. They felt that by clicking on the link they would end up on an affiliate or spam site and may get caught in a never-ending cascade of pop-up windows. Searchers were very wary. In the US, this attitude began to change as known brands began to adopt search.

If Google can't attract the right advertisers that also means that the organic search results in that geographic market are likely easy to manipulate. In many underdeveloped markets around the world, PPC offers greater opportunity than SEO because their is virtually no competition, but as the markets mature and margins get squeezed, doing SEO and owning a brand becomes more profitable than PPC. Either way you approach it, if you can compete on Google.com you should be able to dominate foreign markets. The only issue is scale.
Estimating Market Scale

Google offers an ad preview tool to show you what ads look like in various markets, and you can take advantage of their traffic estimator tool to estimate the size of a market.
If you are in a market dominated by engines other than Google (like China and Russia) then of course you have to use tools other than Google to estimate the size of the market.
How to View US Google Search Results

If you are international and do not want to get redirected to your local version of Google you can view Google.com's results by going to Google.us. While on Google.com you can append &gl=us to see the related US targeted ads. Another option to view international Google search results by using this Google global Firefox Extension or use Joost's plugins that turn off personalization.
How Google Makes Lazy US Only Advertisers Buy Foreign Traffic

While in the Philippines I have noticed that some $20 keywords (in the US) have few advertisers here, and many of the ads are for garbitrage websites. For example, one page advertising on student loans went to a page with stolen content, and had a page title about mesothelioma. If an advertiser choses US only search distribution but opts into the content network they are probably paying for exposure on that page.
When I switched Google to only search local pages the number 1 ranked page for online degrees was an off topic forum thread. Limited competition means great opportunity for those who understand the local culture and are able to gain international recognition.


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