In the Aussie version of Google they have opted to use a tracking URL variable rather than the Javascript model as discussed above. Check out http://www.google.com.au and run a search for your keywords of choice.

The anchor tags for SERPs include
http://www.google.com.au/url?sa=U&st...age.htm&e=7249

I can't explain why Google has elected to run this style of tracking in Australia, but it does prove Google is serious about tracking CTs on SERPs.

One alternate view to those expressed above could be that Google is tracking CTs so they may lower rankings on popular sites (getting the clicks) so those sites are forced to take up AdWords to maintain traffic.