Okay to clear this up this much debated issue! I am UK and this is from the email I received following first transaction through this IPN:
"During our recent review, we found that you have processed at least one
transaction through Google Checkout. However, we were unable to locate
Google Checkout buttons on your website.
As outlined in our programme policies at
https://checkout.google.com/seller/policies.html, you must ensure Google
Checkout buttons or Buy Now buttons are available on your website before
any registration or sign-in pages.
Because it appears that your website does not meet this policy
requirement, your AdWords ads are not eligible to display Google Checkout
badges at this time. (Your account is still active, however and you may
continue to process transactions.)
If you would like to display Google Checkout badges again, you may update
your website in order to meet this requirement. After you update your
site, please reply to this message so we can confirm the changes."
So I can use to process payments but cannot display a badge on my adwords. Hope this helps.