[google.com...]
The problem I see is relevance - Google might not permit a seemingly irrelevant ad, and even if it snuck past their screens you might experience such low clickthroughs that your ad wouldn't be displayed.
Even if your market potential is "wide open", I'd recommend starting with highly relevant searches and, based on what you find, expanding from there.
mannygunn, a keyword will be disabled after 1000 impressions if the CTR standard has not been reached. And an extremely popular search term can literally get 1000 impression in a minute or two as a broad match.
So, in a sense, no harm in trying - but I would be surpised if it were to work well, or to deliver you pre-qualified customers.
Use Keyword Search Tool.It's wonderfull option.
Select the top 5 keywords which are relevant to your site.
Use exact match[keyword], check CTR's , check converstion rate.
Delete Low CTR keywords, expand to "keyword" for the top converting keywords.
Check CTR again it gives you clear picture of what traffic is converting.
Then you can start focussing on what country it is working and what country it is not working.This you can do with division of campaign's wrt Country.
The science of Keyword Analysis and Optimization. :)
...google checks relevancy of the ad by sending spider and analysing your site. So as long as your prepare nice landing page which will be relevant to your adword keywords, your ad, and your site that should be OK.
Actually, this is not correct. Ads are reviewed by actual human beings to make sure that they are relevant to the keywords, and that they meet the other Editorial Guidelines.
And keywords are disabled by pure math. Simply stated, if the keyword doesn't meet the CTR standard, it is disabled. No spidering involved, and no human decision-making.
IMO, keywords destined to deliver good results are keywords that accurately and specifically describe your product or service. Specific keywords are usually much more successful than 'what if' keywords.
Here is an example of using a 'what if' keyword: "I'm selling off road truck tires, and maybe people searching on the keyword 'air' might click on my ad, because tires have air. So I'll use the keyword 'air' and see what happens."
Here is an example of using a specific keyword: "I'm selling off road truck tires, so I'll use the keyword 'off road truck tires'. That way, I'll get a pre-qualified customer who is looking for exactly what I've got." ;)
Every new or edited ad is actually reviewed by a real person. The reviewer checks your ad (and your site as well) to make sure that everything is in line with the Editorial Guidelines.
By the way, there is a link to the Editorail Guidelines at the bottom of every page in your account. Not a bad idea to read them from time-to-time, as they do evolve.