Seem's I've been too busy the last few weeks. Great post!
If you are doing business in foreign countries, make sure you use proxies in that country when trying to see your competitors ad's.
I'm based in a European country. Even if I'm smart enough to go to google.com and search for the English version of our widgets, only 1 ad appears along with mine.
Now I'm using a proxy server which is based in the USA. I reload the page, and all of a sudden I have a whole bunch of ads comes up I've never seen before.
Guess what happens when I switch to a proxy in Canada: only a few of the ads remain - so not all advertisers have thought of doing business in Canada as well...
The reason behind all this is of course the geotargeting in the campaigns. If I'm using the browser, Google KNOWS where I'm located due to my IP address. So if my competitor in the USA has said "United States only", I'll never see his ads appear when surfing from Europe. Unfortunately, the Canadian guy doesn't see them either...
By use of a local proxy, you can act like an imposter and appear to Google as if you were located in the USA (or Canada, for the sake of the example). So make sure you gather some "intelligence" from different countries.
You can find lists of open proxy servers on the net for example at proxy4free.com, and there's even applications which allow you to easily switch proxies instead of doing it manually.
Hope that helps!