Any idea on how to add statistic such as how many clicks per ad?
I would simply install the google analytics module to track clicks.
Yes, as cjdavis says, you could use Google analytics, or any one of the numerous statistics packages out there. This is out of the scope of this module, so I'm marking this as won't fix.
I assume by referring to using google analytics to track clicks you are referring to(?) http://www.google.com/support/googleanalytics/bin/answer.py?hl=en&answer...
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