I *almost* wrote a post about how shocked I was when I clicked on an Adsense ad (a product I was actually interested in) the other day and was redirected to one of these horrible “get a free ipod if you just sell your soul, your email address and send this to 50 of your friends” promos…because apparently the offer was not “good” in Canada. My first reaction was — hello? Anyone heard of Geotargeting? But then I figured it was pre-meditated as they had already planned for the redirect. I really didn’t know what to think.

On a side note, you have a good point about message match becoming more difficult for the long tail. Really the best way to do it is to have one ad group for each product, and have ad groups for category pages too. For example:

Blenders – blender category landing page
Osterizer blender – Osterizer blenders page
Osterizer blender Model #Whatever – Product page

And always triple check your keyword-to-ad-to-landing page accuracy!