I just took at look at my web proxy and noticed that "Ads by Google" had been replaced with an image that said the same thing. it had a white background, black text, and a green, yellow, and red arrow pointing to "Ads by Google". Unfortunately, I was stupid and refreshed the page to see if it would appear again. It didn't come back and I didn't get a screenshot .
There is another screenshot here. If I find it I'll point you to the thread. It appears Google IS testing this. I'm not a huge fan though. Edit: Here's the link: http://forums.digitalpoint.com/showthread.php?t=194224&highlight=Google+test Skinny
yah.. two other threads about this already.. It kinda sucks because the Google image is white, regardless of the background of your ads - totally breaks your 'blending' ..