directwheels - 2:33 am on Jun 2, 2011 (gmt 0)
Yes, CTR does go up with the Google Checkout logo on Adwords.
But, unless you have really happy customers all the time, you will hate their customer feedback portion of it. As usual, it's hard to get happy customers to give feedback but the unhappy ones will always use it to vent.
Then your rating will appear next to your Google Checkout logo in Adwords and you will want to stop using them. At least that's my experience.